Android 4.4 KitKat and Updated Developer Tools

Posted by Dave Burke, Engineering Director, Android Platform



Today we are announcing Android 4.4 KitKat, a new version of Android that brings great new features for users and developers.



The very first device to run Android 4.4 is the new Nexus 5, available today on Google Play, and coming soon to other retail outlets. We’ll also be rolling out the Android 4.4 update worldwide in the next few weeks to all Nexus 4, Nexus 7, and Nexus 10 devices, as well as the Samsung Galaxy S4 and HTC One Google Play Edition devices.



As part of this release, we kicked off Project Svelte, an effort to reduce the memory needs of Android so that it can run on a much broader range of devices, including entry-level devices that have as little as 512MB RAM. From the kernel to system, frameworks, and apps, we've reduced memory footprint and improved memory management so Android can run comfortably on only 512MB of RAM. We did this not only on Android but across Google apps, like Chrome and YouTube.



By supporting a broader range of devices, Android 4.4 will help move the Android ecosystem forward. Now all users will be able to enjoy the very best that Android has to offer, on the devices that best meet their needs.



Here’s a quick look at some of the new features for developers:




  • New ways to create beautiful apps — A new full-screen immersive mode lets your app or game use every pixel on the screen to showcase content and capture touch events. A new transitions framework makes it easier to animate the states in your UI. Web content can take advantage of a completely new implementation of WebView built on Chromium.


  • More useful than ever — A printing framework lets you add the convenience of printing to your apps. A storage access framework makes it easier for users find documents, photos, and other data across their local and cloud-based storage services. You can integrate your app or storage service with the framework to give users instant access to their data.


  • Low-power sensors — New hardware-integrated sensors let you add great new features to your apps without draining the battery. Included are a step detector and step counter that let you efficiently track of the number of walking steps, even when the screen is off.


  • New media capabilities — A new screen recorder lets you capture high-quality video of your app directly from your Android device. It's a great new way to create walkthroughs, tutorials, marketing videos, and more. Apps can use adaptive playback to offer a significantly better streaming video experience.


  • RenderScript in the NDK — A new C++ API in the Android Native Development Kit (NDK) lets you use RenderScript from your native code, with access to script intrinsics, custom kernels, and more.


  • Improved accessibility support — New system-wide captioning settings let your apps present closed captions in the style that's preferred by the user.




There's a lot more, so be sure to check out the Android 4.4 platform highlights for a complete overview of those and other new capabilities for developers. For details on the APIs and how to use them, take a look at the API Overview or watch one of the new DevBytes videos on KitKat.



Along with the new Android 4.4 platform we're releasing a new version of the Android NDK (r9b). The new NDK gives you native access to RenderScript and other stable APIs in Android 4.4, so if you've been waiting to use RenderScript from your native code, give it a try.



Last, we've updated the Support Package (r19) with a new helper library for printing images through the new printing framework, as well as other updates.



You can get started developing and testing on Android 4.4 right away, in Android Studio or in ADT/Ant. You can download the Android 4.4 Platform (API level 19), as well as the SDK Tools, Platform Tools, and Support Package from the Android SDK Manager.




Google Play Services 4.0

Today we're launching a new release of Google Play services. Version 4.0 includes the Google Mobile Ads SDK, and offers improvements to geofencing, Google+, and Google Wallet Instant Buy APIs.



With over 97% of devices now running Android 2.3 (Gingerbread) or newer platform versions, we’re dropping support for Froyo from this release of the Google Play services SDK in order to make it possible to offer more powerful APIs in the future. That means you will not be able to utilize these new APIs on devices running Android 2.2 (Froyo).



We’re still in the process of rolling out to Android devices across the world, but you can already download the latest Google Play services SDK and start developing against the new APIs using the new Android 4.4 (KitKat) emulator.



Google Mobile Ads



If you’re using AdMob to monetize your apps, the new Google Mobile Ads SDK in Google Play services helps provide seamless improvements to your users. For example, bug fixes get pushed automatically to users without you having to do anything. Check out the post on the Google Ads Developer Blog for more details.



Maps and Location Based Services



The Maps and Geofencing APIs that launched in Google Play services 3.1 have been updated to improve overall battery efficiency and responsiveness.



You can save power by requesting larger latency values for notifications alerting your app to users entering or exiting geofences, or request that entry alerts are sent only after a user stays within a geofence for a specified period of time. Setting generous dwell times helps to eliminate unwanted notifications when a user passes near a geofence or their location is seen to move across a boundary.



The Maps API enhances map customization features, letting you specify marker opacity, fade-in effects, and visibility of 3D buildings. It’s also now possible to change ground overlay images.



Google+ and Google Wallet Instant Buy



Apps that are enabled with Google+ Sign-In will be updated with a simplified sign-in consent dialog. Google Wallet Instant Buy APIs are now available to everyone to try out within a sandbox, with a simplified API that streamlines the buy-flow and reduces integration time.



Google Wallet Instant Buy also includes new Wallet Objects, which means you can award loyalty points to a user's saved rewards program ID for each applicable Google Wallet Instant Buy purchase.



New user control over advertising identifier



To give users better controls and to provide you with a simple, standard system to continue to monetize your apps, this update contains a new, anonymous identifier for advertising purposes (to be used in place of Android ID). Google Settings now includes user controls that enable users to reset this identifier, or opt out of interest-based ads for Google Play apps.



More About Google Play Services



To learn more about Google Play services and the APIs available to you through it, visit the Google Services area of the Android Developers site.




Making your App Content more Accessible from Google

Posted by Chaesang Jung, Software Engineer



There are many reasons to build or not to build a mobile app as part of your broader mobile strategy. For instance, while apps offer a rich user experience, users can’t access them through Google Search like they do websites. Today, we’re announcing a new Google Search capability, app indexing, that will start to make apps more accessible through Google on Android.



Let’s say that a user is searching for a movie. With app indexing, Google will begin to include deep links to apps in Android search results. When the user taps on the “Open in app” deep links, the app opens up directly to the movie in question.





In this example, in order for the app deep links to appear in search results,



  • The Flixster app supports deep linking

  • The Rotten Tomatoes website has specified that the Flixster app page is an alternate for the web page

  • Google has indexed the Flixster app to determine relevance

  • The user has installed the Flixster app



The end result is that users will have a seamless search experience when accessing your app content through Google.



Google is currently testing app indexing with an initial group of developers including AllTheCooks, AllTrails, Beautylish, Etsy, Expedia, Flixster, Healthtap, IMDb, moviefone, newegg, OpenTable, Trulia, and Wikipedia. Deep links for these applications will start to appear in Google search results on Android, in the US, in a few weeks.



How to get started



If you are interested in enabling indexing for your Android app, you can learn more about our developer guidelines at developers.google.com/app-indexing and sign up. We are expanding our app indexing efforts and will gradually include more developers over time.




Getting Your SMS Apps Ready for KitKat


Posted by Scott Main and David Braun



Sending and receiving SMS messages are fundamental features on mobile devices and many developers have built successful apps that enhance this experience on Android. Some of you have built SMS apps using hidden APIs—a practice we discourage because hidden APIs may be changed or removed and new devices are not tested against them for compatibility. So, to provide you with a fully supported set of APIs for building SMS apps and to make the user experience for messaging more predictable, Android 4.4 (KitKat) makes the existing APIs public and adds the concept of a default SMS app, which the user can select in system settings.



This means that if you are using the hidden SMS APIs on previous platform versions,
you need to make some adjustments so your app continues to work when Android 4.4 is released later this year.




Make your app the default SMS app





On Android 4.4, only one app can receive the new SMS_DELIVER_ACTION intent, which the system
broadcasts when a new SMS message arrives. Which app receives this broadcast is determined by
which app the user has selected as the default SMS app in system settings. Likewise, only the
default SMS app receives the new WAP_PUSH_DELIVER_ACTION intent when a new MMS arrives.



Other apps that only want to read new messages can instead receive the SMS_RECEIVED_ACTION broadcast intent when a new SMS arrives. However, only the app that receives the SMS_DELIVER_ACTION broadcast (the user-specified default SMS app) is able to write to the SMS Provider defined by the android.provider.Telephony class and subclasses. As such, it's important that you update your messaging app as soon as possible to be available as a default SMS app, because although your existing app won't crash on an Android 4.4 device, it will silently fail when attempting to write to the SMS Provider.



In order for your app to appear in the system settings as an eligible default SMS app, your manifest file must declare some specific capabilities. So you must update your app to do the following things:




  • In a broadcast receiver, include an intent filter for SMS_DELIVER_ACTION ("android.provider.Telephony.SMS_DELIVER"). The broadcast receiver must also require the BROADCAST_SMS permission.

    This allows your app to directly receive incoming SMS messages.



  • In a broadcast receiver, include an intent filter for WAP_PUSH_DELIVER_ACTION ("android.provider.Telephony.WAP_PUSH_DELIVER") with the MIME type "application/vnd.wap.mms-message". The broadcast receiver must also require the BROADCAST_WAP_PUSH permission.

    This allows your app to directly receive incoming MMS messages.



  • In your activity that delivers new messages, include an intent filter for ACTION_SENDTO ("android.intent.action.SENDTO") with schemas, sms:, smsto:, mms:, and mmsto:.

    This allows your app to receive intents from other apps that want to deliver a message.



  • In a service, include an intent filter for ACTION_RESPONSE_VIA_MESSAGE ("android.intent.action.RESPOND_VIA_MESSAGE") with schemas, sms:, smsto:, mms:, and mmsto:. This service must also require the SEND_RESPOND_VIA_MESSAGE permission.

    This allows users to respond to incoming phone calls with an immediate text message using your app.





For example, here's a manifest file with the necessary components and intent filters:


<manifest>
...
<application>
<!-- BroadcastReceiver that listens for incoming SMS messages -->
<receiver android:name=".SmsReceiver"
android:permission="android.permission.BROADCAST_SMS">
<intent-filter>
<action android:name="android.provider.Telephony.SMS_DELIVER" />
</intent-filter>
</receiver>

<!-- BroadcastReceiver that listens for incoming MMS messages -->
<receiver android:name=".MmsReceiver"
android:permission="android.permission.BROADCAST_WAP_PUSH">
<intent-filter>
<action android:name="android.provider.Telephony.WAP_PUSH_DELIVER" />
<data android:mimeType="application/vnd.wap.mms-message" />
</intent-filter>
</receiver>

<!-- Activity that allows the user to send new SMS/MMS messages -->
<activity android:name=".ComposeSmsActivity" >
<intent-filter>
<action android:name="android.intent.action.SEND" />
<action android:name="android.intent.action.SENDTO" />
<category android:name="android.intent.category.DEFAULT" />
<category android:name="android.intent.category.BROWSABLE" />
<data android:scheme="sms" />
<data android:scheme="smsto" />
<data android:scheme="mms" />
<data android:scheme="mmsto" />
</intent-filter>
</activity>

<!-- Service that delivers messages from the phone "quick response" -->
<service android:name=".HeadlessSmsSendService"
android:permission="android.permission.SEND_RESPOND_VIA_MESSAGE"
android:exported="true" >
<intent-filter>
<action android:name="android.intent.action.RESPOND_VIA_MESSAGE" />
<category android:name="android.intent.category.DEFAULT" />
<data android:scheme="sms" />
<data android:scheme="smsto" />
<data android:scheme="mms" />
<data android:scheme="mmsto" />
</intent-filter>
</service>
</application>
</manifest>



Any filters for the SMS_RECEIVED_ACTION broadcast in existing apps will continue to work the same on Android 4.4, but only as an observer of new messages, because unless your app also receives the SMS_DELIVER_ACTION broadcast, you cannot write to the SMS Provider on Android 4.4.



Beginning with Android 4.4, you should stop listening for the SMS_RECEIVED_ACTION broadcast, which you can do at runtime by checking the platform version then disabling your broadcast receiver for SMS_RECEIVED_ACTION with PackageManager.setComponentEnabledSetting(). However, you can continue listening for that broadcast if your app needs only to read special SMS messages, such as to perform phone number verification. Note that—beginning with Android 4.4—any attempt by your app to abort the SMS_RECEIVED_ACTION broadcast will be ignored so all apps interested have the chance to receive it.



Tip: To distinguish the two SMS broadcasts, imagine that the SMS_RECEIVED_ACTION simply says "the system received an SMS," whereas the SMS_DELIVER_ACTION says "the system is delivering your app an SMS, because you're the default SMS app."





Disable features when not the default SMS app



In consideration of some apps that do not want to behave as the default SMS app but still want to send messages, any app that has the SEND_SMS permission is still able to send SMS messages using SmsManager. If and only if an app is not selected as the default SMS app on Android 4.4, the system automatically writes the sent SMS messages to the SMS Provider (the default SMS app is always responsible for writing its sent messages to the SMS Provider).



However, if your app is designed to behave as the default SMS app, then while your app is not selected as the default, it's important that you understand the limitations placed upon your app and disable features as appropriate. Although the system writes sent SMS messages to the SMS Provider while your app is not the default SMS app, it does not write sent MMS messages and your app is not able to write to the SMS Provider for other operations, such as to mark messages as draft, mark them as read, delete them, etc.





So when your messaging activity resumes, check whether your app is the default SMS app by querying Telephony.Sms.getDefaultSmsPackage(), which returns the package name of the current default SMS app. If it doesn't match your package name, disable features such as the ability for users to send new messages.



When the user decides to use your app for messaging, you can display a dialog hosted by the system that allows the user to make your app the default SMS app. To display the dialog, call startActivity() with the Telephony.Sms.Intents.ACTION_CHANGE_DEFAULT intent, including an extra with the Sms.Intents.EXTRA_PACKAGE_NAME key and your package name as the string value.



For example, your activity might include code like this:



public class ComposeSmsActivity extends Activity {

@Override
protected void onResume() {
super.onResume();

final String myPackageName = getPackageName();
if (!Telephony.Sms.getDefaultSmsPackage(this).equals(myPackageName)) {
// App is not default.
// Show the "not currently set as the default SMS app" interface
View viewGroup = findViewById(R.id.not_default_app);
viewGroup.setVisibility(View.VISIBLE);

// Set up a button that allows the user to change the default SMS app
Button button = (Button) findViewById(R.id.change_default_app);
button.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
Intent intent =
new Intent(Telephony.Sms.Intents.ACTION_CHANGE_DEFAULT);
intent.putExtra(Telephony.Sms.Intents.EXTRA_PACKAGE_NAME,
myPackageName);
startActivity(intent);
}
});
} else {
// App is the default.
// Hide the "not currently set as the default SMS app" interface
View viewGroup = findViewById(R.id.not_default_app);
viewGroup.setVisibility(View.GONE);
}
}
}



Advice for SMS backup & restore apps



Because the ability to write to the SMS Provider is restricted to the app the user selects as the default SMS app, any existing app designed purely to backup and restore SMS messages will currently be unable to restore SMS messages on Android 4.4. An app that backs up and restores SMS messages must also be set as the default SMS app so that it can write messages in the SMS Provider. However, if the app does not also send and receive SMS messages, then it should not remain set as the default SMS app. So, you can provide a functional user experience with the following design when the user opens your app to initiate a one-time restore operation:





  1. Query the current default SMS app's package name and save it.
    String defaultSmsApp = Telephony.Sms.getDefaultSmsPackage(context);



  2. Request the user change the default SMS app to your app in order to restore SMS messages (you must be the default SMS app in order to write to the SMS Provider).
    Intent intent = new Intent(context, Sms.Intents.ACTION_CHANGE_DEFAULT);
    intent.putExtra(Sms.Intents.EXTRA_PACKAGE_NAME, context.getPackageName());
    startActivity(intent);



  3. When you finish restoring all SMS messages, request the user to change the default SMS app back to the previously selected app (saved during step 1).
    Intent intent = new Intent(context, Sms.Intents.ACTION_CHANGE_DEFAULT);
    intent.putExtra(Sms.Intents.EXTRA_PACKAGE_NAME, defaultSmsApp);
    startActivity(intent);




Prepare to update your SMS app


We encourage you to update your apps as soon as possible to provide your users the best experience on Android. To help you make the changes, we'll soon be providing the necessary SDK components for Android 4.4 that allow you to compile and test your changes on Android 4.4. Stay tuned!



Tablet changes in Google Play coming up November 21

Posted by Ellie Powers, Google Play team



Fueled by the Nexus 7 and other great devices, more than 70 million Android tablets have been activated. Thousands of developers have already designed their apps to look great on tablets, and with the holidays fast approaching, we’re making it even easier for the next wave of tablet owners to discover great apps and games.



Play Store tablet changes coming up on November 21



Earlier this year, Google Play added a “designed for tablets” section, where users could easily discover apps that look great on their 7”- and 10”-tablets. This section includes only apps and games which meet criteria and guidelines we established last year. (Here’s an overview if you missed it.) Developers who invest the time to meet the criteria are seeing great results; take Remember The Milk, which saw an 83% increase in tablet downloads from being in this section. (see the whole story here).



On November 21, the Play Store will make a series of changes so it’s even easier for tablet users to find those apps that are best for their devices. First, by default, users browsing Google Play on a tablet will now see apps and games that are designed for tablets on the top lists (Top Paid, Top Free, Top Grossing, Top New Paid, Top New Free, and Trending). Tablet users will still be able to switch the view so they can see all apps or games if they choose. Also starting November 21, apps and games that do not meet the “designed for tablets” criteria will be marked as “designed for phones” for users who browse the Play Store on tablets.



You’ll want to make sure that your app is designed for tablets; read more about how to do this at the end of this blog post.





Make sure your app is ready!



If you want to be sure your app is included in the “Designed for tablets” view in time for the November 21 Play Store changes, go to the Developer Console to check your tablet optimization tips. If you see any issues listed there, you’ll need to address them in your app and upload a new binary for distribution. If there are no issues listed, your app is eligible to be included in the “Designed for tablets" view in the top lists.





Also, make sure to read the full tablet quality checklist to understand how to build outstanding tablet experiences.



Everyday, thousands of Android developers are taking advantage of the tremendous Android tablet opportunity. The flood of new users coupled with the increased screen size means new user experiences, more engagement and more monetization opportunities. We’re excited to see what you do!