How Do I Use the Eyes-Free Shell?

The eyes-Free Shell is an alternative home screen or launcher for drivers and other people who don’t or can’t look at the screen. It gives blind and visually impaired users a way of interacting with the touch screen to check status information, launch other applications, and direct dial or message a contact.

This post is about the Shell's main screen. For information about the Shell's various shortcuts screens, which can be set up to launch other apps, visit bookmarked URLs, open the Details screen for individual contacts, access Eyes-Free Shell widgets, direct dial or message contacts, and quickly move to items within the phone's settings menu, refer to the next post.

Finding the Eyes-Free Shell Main Screen

The Eyes-Free Shell has several parts. The main screen has 7 widgets or mini-apps that offer users quick access to information like time and battery status. It is the screen that opens when the Shell is launched. For information on setting the eyes-Free Shell as the default home screen, refer to the previous post.

In addition to the main screen, the Shell has at least 2 other pages (called menus), where users can place shortcuts to things they use frequently. In fact, if the Shell appears to be blank as users attempt to interact with it, the likely reason is that they are on one of the shortcuts pages, not the main screen.

To return to the main screen of the Eyes-Free Shell, do the following:

1. Touch the left or right edge of the screen.
a. If the phone is in portrait orientation, touch the literal left and right edges of the screen, the glass surface near the plastic or metal casing that holds it in place.
b. If the phone is in landscape orientation, touch the screen along imaginary lines that are about 1 inch or 2.5 cm from the literal left and right edges of the glass surface. When auto rotate is turned off, the phone is in landscape orientation only when the hardware keyboard is pulled out. The literal left edge of the screen is the space ordinarily occupied by the status bar (which does not behave like a status bar in this situation), and the literal right edge of the screen is occupied by the Back, Home, Menu, and Search soft keys.
2. Touch the same edge of the screen repeatedly to cycle through the shortcuts pages, stopping when you hear, "Home."

By default, the pages are Home, Shortcuts Left, and Shortcuts Right. Names can be changed to reflect their content, and more pages can be added.

Interacting with the Eyes-Free Shell

On the Eyes-Free shell, the 7 mini-apps or widgets are arranged in 3 rows of 3, as in a tick-tack-toe game, a 3 by 3 grid, or the top 9 keys of a standard telephone dialing keypad. When the phone is closed (i.e., the keyboard is tucked under the touch screen), the grid is used with the phone in portrait orientation. When the phone is open (i.e., the physical keyboard is available to the user), the grid is oriented to landscape.

This grid isn’t at a fixed location; rather, its center is wherever the screen is touched first. Using the telephone keypad analogy, that center point is the 5 key, and users must stroke vertically up or down, horizontally left or right, or diagonally in any direction to reach another one of the keys on the phone.

When another "key" is reached, the phone vibrates and speaks the name of the widget being touched. To access the widget, users simply break contact with the screen.

For best results with the Eyes-Free shell:

1. Touch the screen in the general center, not close to the edges. Some users touch the phone with the index finger; others use the middle finger, as when they touch a telephone keypad.
2. Move your finger at a moderate rate, neither slow nor fast.
3. Use the vibrations to confirm that you have moved to a new key position. The phone vibrates when you touch the screen, thus identifying the 5 position. It vibrates again as you move to a new key. If you continue to hold your finger in that position, the name of the function is spoken (e.g., time in the 2 position or Battery in the 3 position).
4. Avoid touching the right and left edges of the screen as doing so moves you to a shortcut page. If you touch the edge of the screen by accident, touch the edge again repeatedly until you cycle back to the main screen.
5. Set the Talkback keyboard to Hidden with a long-press of the volume buttons if the Shell is behaving strangely.

Noting Keyboard Behavior While in the Eyes-Free Shell

While the eyes-Free shell, the Eyes-Free shortcuts, and the Talking Dialer screens are open, the physical controls on the keyboard do not behave in the usual way. Most physical controls are unresponsive while in the Shell and Shortcuts, and in Dialer, arrow keys are unresponsive and different characters are assigned to the typing keys.

The following set of keys can be used with the following results:

1. Back works as expected. A short press moves focus to the previous screen. A long press moves focus to the stock Home screen.
2. Home works as expected. A short press moves focus to the Eyes-Free shell. A long press moves focus to the Recent Applications screen.
3. Menu enables editing of the Eyes-Free Shell main screen and of its shortcut screens.
4. Search moves focus to the Talking Dialer. If the Talking Dialer is not installed, The phone announces, "Application is not installed."
5. The quick launch Search+letter works as expected, opening the app assigned to the Android shortcut.
6. The Talkback keyboard should be set to Hidden when working with the Eyes-Free Shell and its shortcut screens.

Using the Widgets on the Eyes-Free Shell

These are instructions for using the widgets available through the Eyes-Free shell:

1. For signal strength and network information, use Steps a and b below. This information is also available by going to Settings/About Phone/ Status, Phone Number, Signal, etc.
a. Up-stroke diagonally to the left to reach the 1 position. The phone announces, "Signal."
b. Lift your finger.
2. For the time, use Steps a and b below. This information is also available by going to Settings/Date and time.
a. Up-stroke vertically to reach the 2 position. The phone announces, "Time."
b. Lift your finger.
3. For battery status information, use Steps a and b below. This information is also available by going to Settings/About Phone/ Status, Phone Number, Signal, etc.
a. Up-stroke diagonally to the right to reach the 3 position. The phone announces, "Battery."
b. Lift your finger.
4. No widget is assigned to the 4 position. This is a useful spot for a frequently used app that requires minimal keyboarding, like Talking compass (by Bill Ray), Intersection Explorer (by Eyes-Free Project), or Checkmark Calendar (by Greenbean Soft).
5. No widget is assigned to the 5 position since it is what determines the relative placement of the other keys. To avoid activating any widget , stroke back to this key and lift your finger. The phone announces, "Home.
6. For information about your current location, use the steps listed below. Repeating the steps produces varying results, alternating between a GPS and a network location. This type of information is also available from Google Maps and other GPS apps, like WalkyTalky by Eyes-Free Project and Location Blind by Bill Ray, available through the Android Market.
a. Side-stroke to the right to reach the 6 position. The phone announces, "Location."
b. Lift your finger.
c. Wait a few seconds for the phone to announce location details.
7. For voicemail, use the steps listed below. This is also available by dialing your carrier's voicemail code (e.g., *86 for Verizon customers), using any of the calling methods described in other posts.
a. Down -stroke diagonally to the left to reach the 7 position. The phone announces, "Voicemail."
b. Lift your finger.
c. Use the physical keyboard to enter your password, and continue with voicemail, using the physical keyboard to enter menu choices. If the number row doesn't behave as expected, try pressing the alt or shift key before typing each number.
8. For a vertical list of All Apps, use the steps listed below. The stock Home screen also includes an All Applications or Sliding Drawer icon, which provides access to all the apps on the phone, presented alphabetically in a grid, so users must remember to arrow left and right as well as up and down.
a. Down-stroke vertically to reach the 8 position. The phone announces, "Applications."
b. Lift your finger.
c. An alphabetical list of all of the apps appears on the screen. Find and enter the application by doing one of the following:
i. Type the first letter of the app you want to use. If the names of several apps begin with that letter, arrow down to find the second, third, and so on. If you meant to type a different letter, arrow up or down once, then type another letter. When the app is located, press Enter, the selector, or the Search button to open it.
ii. Use Stroke dialing.
9. For simple voice searches, use One Vox. Voice searches can also be made from the stock Home screen by long pressing the Search button; however, this feature appears to be mostly inaccessible at this time.
a. down-stroke diagonally to the right to reach the 9 position. The phone announces, "Search."
b. Lift your finger. A soft click is played.
c. Say a search term. Speak at a moderate conversational rate, without pausing between serch terms. Examples of search terms are detailed in another section of this post.
d. Wait for the phone to announce the results. Results are returned quickly. If no results are returned in 10 seconds, press Back briefly and try again, or use the physical navigational controller to scroll to the Speak Again or Cancel button, press the selector, and speak or move on to another activity.

Adjusting screen reader volume with the Eyes-Free Shell

One of the perks of the eyes-Free Shell is that users can adjust screen reader volume while the phone is silent. To do this:

1. Place your finger on the Eyes-Free Shell. A thumb works well for this, with the middle, ring, and pinky fingers under the handset.
2. Press the volume-up/down key repeatedly while your finger is on the screen. The phone beeps more loudly or more softly with each press of the volume control.

Accessing an App's Details Screen from the Eyes-Free Shell

Another perk of the Eyes-Free Shell is that users can quickly launch the details screen for an app. This screen is where users uninstall apps and perform other maintenance tasks, like force closing a troublesome app or clearing defaults so a different app can be launched automatically in certain situations. Normally, getting to that screen involves going into Settings/Applications/Manage Applications, but with the Shell, the process is much shorter.

1. Down-stroke to the 8 position to launch the Applications widget.
2. Scroll to the app, or use first-letter navigation to find it in the list.
3. Press the Menu button.
4. Do one of the following:
a. Scroll to and press the selector on Details to open the details screen. The options on this screen are not arranged in a list; to find your option scroll left and right as well as up and down. Options are Clear Cache, Clear Data, Clear Defaults, Force Stop, Move to SD card, Uninstall.
b. Scroll to and press the selector on Uninstall to uninstall the app.
5. Press Back if necessary when you're done.

Finding Quick Answers with Eyes-Free Voice Search

Users can take advantage of some of Google’s search features to find quick answers in OneVox, the simple voice search app of the Eyes-Free shell. Examples of search terms are listed below. The order of the items in the search string doesn’t seem to matter: users can say, "weather. Mountain View" or "Mountain View weather," to get the same result.

• Calculations – To hear the results of an addition, subtraction, multiplication, division, or percentage problem, say the calculation you'd like done. Examples: 3 plus 4, 20 minus 6, 5 times 8, 39 divided by 13, 20 percent of 3,495.
• Currency Conversion – To hear money equivalents between countries, say, the source currency, the word "in," and the target currency. Example: 100 U.S. dollars in Mexican pesos.
• Dictionary Definitions – To hear a definition for a word or phrase, say, "define" or "definition," and word(s): Example: define, dog.
• Sunrise & Sunset – To hear the precise times of sunrises and sunsets for many U.S. and world cities, say, "sunrise" or "sunset," and the city name. Example: Sunset, San Jose, Costa Rica.
• Time – To hear the time in many cities around the world, say, "time," and the name of the city. Example: time, Madrid.
• Unit Conversion – To hear the equivalents between many different units of measure for distance, height, volume, weight, and more, say the source unit, the word "in," and the target unit. Examples: 40 miles in kilometers, 3 ounces in grams, 1 gallon in liters.
• Weather – to hear the weather for many U.S. and world cities, say, "weather," and the city and state, the U.S. zip code, or the city and country. Example: weather, London, England.

How Do I Set or Change the Default Home Screen?

When the phone has two applications that do the same thing, Android wants to know which app should be used. For example, if two or more home screens are installed, pressing the Home button makes Android display a list of available home screens and prompts users to select one. Likewise, users who select the Email option from Contacts are prompted to choose between the stock email app and K-9 Mail, if the latter has been installed from the Market. Users can select the app they want to use this time, or they can select the one they want to use all the time.

This post describes how to tell the phone which of two or more applications to use for a particular task. The steps here describe how to set the default home screen, but the procedure is the same for setting the default email reader, web browser, Twitter client, and so on.

Setting the Default Home Screen from the Android System Screen

Once the Eyes-Free Shell is installed, pressing Home brings up the Android System screen, which allows users to select between the Stock Home screen and the Eyes-Free Shell. It also gives users the option to set the default setting.
1. If necessary, slide the physical keyboard out to access the arrow keys.
2. Briefly press the Home button. The phone may say, "Android system."
3. Navigate through the items on the screen: Eyes-Free, Home, and Use by Default for This Action.
4. Press the selector on Use by Default for This Action.
5. Set your default home screen.
a. If you want your default to be the Eyes-Free shell, arrow to Eyes-Free shell and press the selector.
b. If you want your default to be the stock Home screen, arrow to Home and press the selector
6. Briefly press the Home button to move to the home screen you have selected.

Clearing the Default Home Screen in Settings

If pressing the Home button opens a particular screen, then that home screen has already been set as the default. To set a different default, users must clear the current one. When they do, they can access the Android system screen and follow the steps described above to choose a new default home screen.

1. From the Home screen, go to Settings.
a. On the stock Launcher, press Menu, navigate to Settings, and press the selector.
b. On the Eyes-Free shell, down-stroke to Applications, type S, navigate to Settings if necessary, and press enter.
2. Navigate to Applications and press the selector.
3. Navigate to Manage Applications and press the selector.
4. Focus is on Downloads. At this point, you can arrow down through your installed applications or arrow right to All applications.
a. If your current default is the stock Home screen and you want to change it to Eyes-Free shell, arrow right to All; then arrow down to your Home screen, which may be called "Home" or "Launcher"; Press the selector.
b. If your current default is the Eyes-Free shell and you want to change it to the stock Launcher, Arrow down to Eyes-Free shell, and press the selector.
5. Navigate to Clear Defaults, and press the selector there. This screen is a nonuniform grid, so you may need to navigate in different directions.
6. Briefly press the Home button. Focus should move to the Android System screen, allowing you to use the previous instructions to set your preferred Home screen.

Clearing the Default Home Screen in the Eyes-Free Shell

The Eyes-Free Shell offers a convenient way to clear defaults for most apps on the phone. The stock home screen isn't one of them, so for that app specifically, users need to follow the steps described in the previous section. For most other cases (e.g., setting the default email reader or web browser), the following method is very handy.

1. Go to the Eyes-Free Shell.
a. If the Eyes-Free Shell is your default home screen, press the Home button.
b. If the stock Home screen is your default launcher, press the Home button, Navigate to and press the selector on All Applications, then on Eyes-Free Shell.
2. Down-stroke to the 8 position for Applications.
3. Navigate to the app that is currently the default. Do not press enter.
4. Press the Menu button.
5. Navigate to and press the selector on Details.
6. Navigate to Clear Defaults, and press the selector there. This screen is a nonuniform grid, so you may need to navigate in different directions.

TalkBack, Eyes-Free Shell Refreshed --- Now With End-User Settings

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We are pushing out a series of updates via Android Market for TalkBack and the Eyes-Free Shell. Here is a brief overview of end-user visible changes.

Accessibility Preferences

Going by the principle of things should just work as expected , we have long resisted giving in to having a complex set of user preference settings for TalkBack and friends --- in my experience, if you introduce such a settings menu early on, we as software engineers tend to punt on all complex decisions by turning each question into a complex user-facing dialog. That said, it is now time to gradually introduce end-user settings for some aspects of the various accessibility tools.

Accessibility Preferences

Welcome new application AccessibilityPreferences to Android. What this application does:

• From an end-user perspective, it provides a single place where you will find preference settings corresponding to each accessibility tool you have installed on your phone.
• For developers of accessibility tools, it provides a simple means of registering a custom program for managing end-user preferences for that tool.

TalkBack installs its user preferences under this tool. You can tweak a number of settings that affect TalkBack behavior including:

• Control whether TalkBack speaks when the screen is off --- useful to silence status messages when you have the phone turned off.
• Control whether TalkBack speaks when ringer volume is set to 0, i.e., phone is in silent mode.
• Control whether the proximity sensor is used to shut off speech.

Over time, we'll add more settings here as appropriate --- but expect us to be conservative with respect to how many settings show up.

Updates To The Eyes-Free Shell

Here is a summary of updates to the Eyes-Free Shell:

• Changes the proximity sensor logic so that it is only active when the shell is active; this should be more battery efficient
• Fixes a race condition bug that can trigger when the shell is being exited as an application is being installed/removed

TalkBack

Here is a summary of changes to TalkBack:

• TalkBack now includes application-specific speech strategies for some popular applications. This provides context-sensitive spoken feedback.
• Applications that have such speech strategies defined include Facebook, Stitcher and GoogleVoice amongst others.
• Implements a settings screen that can be used with Accessibility Preferences
• Available settings:
   
  1. Ringer Volume (Speak at all ringer volumes, No speech in Silent Mode, No speech in Vibrate and Silent Mode)
   
  2. Screen Status (Allow speech when screen is off, No speech when screen is off)
   
  3. Speak Caller ID (checked/not checked)
   
  4. Proximity Sensor (checked/not checked)

In addition, TalkBack introduces the ability to add application-specific plugins --- expect to see more advancement here in future releases.

AccessibilityPreferences Hints For Developers

If you're a developer of an AccessibilityService, you need to:

• Implement a preferences screen for your application.
• Implement this with intent filter:

              
  
              <intent-filter>            
  
                  <action android:name="android.intent.action.MAIN" />            
  
                  <category android:name="android.accessibilityservice.SERVICE_SETTINGS" />            
  
              </intent-filter>            
  
          
  

Share And Enjoy,

Eyes-Free Review: Droid2 From MOT

Here is a quick eyes-free access overview of the MOT Droid2.

Hardware

1. The device has a pull-out keyboard, and the buttons are much more tactile than the original Droid.
2. The device also has dropped the hard-to-use D-Pad from the original Droid in favor of PC-style arrow keys.
3. There is once again no dedicated number row at the top.
4. The capacitive buttons on the front of the device appear in a different order from the original Droid --- with the device in portrait mode, reading left to right you have: Menu, home, back, and search.
5. In addition, MOT ships a voice search application on the device that is triggered by pressing a special microphone button -- it's worth learning the position of this key, since voice-search can be useful --- and more importantly, if you're relying on spoken feedback, hitting this button leads to the phone falling inexplicably silent.

Software

If you look under accessibility, you'll find an application called Voice Readouts from MOT. This appears to be a screenreader analogous to TalkBack, though in my experience, it did not produce spoken feedback in many instances. That said, this application collaborates well with TalkBack --- and after installing TalkBack from the Android Market (note: the Droid2 does not come with TalkBack bundled) -- you can activate both TalkBack and VoiceReadout for an optimal experience.

VoiceReadout appears to have a preliminary version of touch-exploration. With VoiceReadout active, a single tap speaks the item under the finger; a double-tap activates that item. Note that moving the finger around on the display does not appear to trigger touch exploration; also, touch exploration appears to be available in only some contexts.

Instances where touch exploration appears to be active

1. Settings application.
2. Portions of Android Market.

In general, touch exploration appears to be available in ListView.

In addition, the Droid2 also includes a low-vision accessibility tool called Zoom Mode ( look for it under Settings -> Accessibility ) this tool provides a magnification lens.

Summary

All in all, the Droid2 appears to be one of the better choices for eyes-free use from among the presently available crop of Android phones. Touch exploration, though preliminary, is nice to see on the platform, and the bundled low-vision magnification aid is a nice touch. Voice Readouts is also a great example of an Android accessibility service done right in that it co-exists peacefully with other screenreaders like TalkBack to provide an optimal end-user experience. To users not familiar with adaptive technologies in general, this might not sound like a big deal --- but users of PC screenreders have long been familiar with the need to have only one screenreader turned on. As we transition to modern platforms like Android, it's useful to remind ourselves that screenreaders can in fact co-exist, with each tool providing something useful to create an overall experience that is greater than the sum of the parts.

Welcoming Loquendo Susan To Android (FroYo)

Android 2.2 (AKA FroYo) introduces many platform enhancements, and one that I find particularly relevant is the ability to plug-in additional Text-To-Speech engines. What this means from an end-user point of view:

• Android comes with a set of built-in voices since Android 1.6 --- these are the Pico voices for English, French, Italian, German and Spanish.
• With the Text-ToSpeech plug-in mechanism in place, we can now add new engines to the platform.
• The first such add-on was ESpeak, which brings support for many of the world's languages.
• And now, vendors are able to sell high-quality add-on voices via the Android Market.
• Loquendo Susan is the first commercially available voice for Android. Users running FroYo can buy this voice on the Android Market. Thanks to the plug-in mechanism, once you buy a new voice, you can switch all your talking applications to use the newly installed voice --- see instructions below.

Activating And Using Newly Installed Voices

Goto Settings → Voice Input And Output → Text To Speech Settings. First, activate the newly installed voice by clicking the corresponding checkbox item for that voice. Next, go to Default Engine in the Text To Speech Settings menu, and make the newly installed voice your default engine. Finaly, if you want all applications to use the new voice, check option Always use my settings

With this in place, my Nexus and Droid both speak using Loquendo Susan --- thus turning my Android into into a truly pleasant eyes-free device.

Stitcher And TalkBack: The World In My Ears

Shortwave Radio --- and DXing was one my hobbies growing up--- I spent many hours listening to far-off radio stations ---and in the process developed a love for languages. Fast forward to the late 90's, and one could now listen to radio stations from all around the world on the Internet --- but this time without the hiss and static of shortwave propogation. But there was a catch --- you needed to be at your computer to listen to these stations. At home, I solved this problem by setting up a set of living room speakers connected to the computer in my office-bedroom; with a wireless keyboard, this brought Internet radio to my living room.

Fast-forward to the next decade, and I now have the Internet in my pocket in the form of a smart phone. I recently discovered Stitcher on the Android Market --- and it got me the final mile to having ubiquitous access to Internet Radio!

Using Stitcher With TalkBack

There is little more to say other than try it out! .Stitcher on Android is a simple Android application that worksout of the box with TalkBack. Once you install stitcher fromMarket, use the arrow keys or trackball on your phone to browse through the various categories. Clicking on stations launchesplayback immediately. Note that for now, the stop buttonin the player is not navigable by the trackball --- I have gotten used to hitting it by dead-reckoning since it always appears in afixed position. In the last few weeks, stitcher hasreplaced StreamFuriously , my previous Internet Radio solution on Android.

So here's to happy listening!A brief note on the title of this post --- The World In My Ears was also the title of abook on DXing by Arthur Cushen from New Zealand --- I remember hearing his voice in the 80's on the BBC's World Service.

An Eyes-Free View Of Android At The Google IO Sandbox

Google IO 2010 is playing home to over 5,000 attendees in San Francisco this week. A number of Google Access engineers are at the conference consuming and producing information --- here is a brief view of some of the exciting bits seen on the Android show floor from an eyes-free perspective.

Hardware And New Devices From An Eyes Free Perspective

Many of the phone manufacturers were showing off their latest devices on the show floor --- visit the Android Sandboxat Google IO to see these first hand. Charles and I walked through the various displays Wednesday (May 19) afternoon to test drive these devices first-hand --- given the large number of Android devices coming out every week, this was a unique opportunity to see many of these devices for the first time. Here are some highlights:

• All devices were running Android 1.6 or later, and consequently, Settings/Accessibility was available on every device. Having worked on this for the last 2 years, it's extremely gratifying to see phone manufacturers including accessibility in their devices.
• We found one device from Motorola where we couldn't find the accessibility setting --- the booth representative promised to check after we pointed this out --- waiting to hear back.
• My favorite device was the LG Ally --- check this device out if you get a chance.
  • Device to be sold by Verizon.
  • Device has an elegant tactual feel.
  • Front of the device sports hardware answer/hangup buttons.
  • The pull-out qwerty keyboard is a pleasure to use --- I would rate this one of the best designed cell phone keyboards I've seen.
• Android devices continue to show up in many shapes and sizes --- re-emphasizing that there is a device for everyone. This makes it even more important to choose a device that meets your particular needs.

Software --- Android Applications Galore

We also visited the various vendors showing off their latest Android applications. What was gratifying was that even though most of these developers had paid little thought to eyes-free use --- and were blissfully unaware of the existence of an Android Accessibility API, their applications worked for the most part with Accessibility enabled. Where there were gaps, we were able to show developers what they needed to do --- everyone was extremely receptive. Below is a brief summary of what we saw --- and a shout-out to all the friendly developers we met:

Where

This is a very accessible application I have been using for a while --- the developers were thrilled to hear that it was accessible since they had made no special effort.

Aloqua

A competing application to Where with a very slick visual UI. This application doesn't raise the appropriate Access Events at present because it's a custom UI. When we first talked to their lead developer he was extremely hesitant saying I dont want to change my custom UI. However, I could hear his face light up when we said You dont need to change your look and feel --- you just need to set a couple of custom Java properties (specifically, property ContentDescription

Pandora

Another favorite of mine that works well with access --- except --- the player controls are unlabeled. I showed them the application in action on my Droid --- looking forward to seeing this application become even more usable.

NPR News

There are many NPR tools on the Android Market --- NPR News is the official application. The application was originally written by a Googler and Open Sourced --- I have been using it for about 4 months and it's completely accessible. It could do with some power-user shortcut keys to make it even more efficient.

MLB At Bat

I had originally played with this application during last year's World Series; at the time, the application was quite usable with TalkBack. I'm happy to report that nothing has regressed --- the application still continues to to work well, except for a couple of glitches with unlabled player controls. The booth representatives had actually heard of accessibility --- and were receptive to fixing the remaining issues.

Summary: The light-weight design of the Android Access layer has proven valuable in making sure that it makes it on to every device. The minimal set of responsibilities the API places on developers has meant that a large number of Android applications are accessible out of the box.