Frequently asked questions

This page contains answers to most commonly asked questions or errors that you may encounter while developing an instant app. For more information about user experience guidelines, see UX best practices for apps on Google Play Instant and UX best practices for games on Google Play Instant.

General

• What devices are supported for Google Play Instant?

  Google Play Instant is supported on the majority of devices running Android 5.0 (API level 21) and higher.

• Do developers need to build two different Android apps?

  Developers only need to maintain a single project with a single source tree. They can configure the project to create two build artifacts:

  • Installable version
  • Instant apps version

  The effort involved in adding instant app support to an installable app depends on how the installable app is currently structured.

  Note: Instant app version must be the same or lesser than the last published installable app version.

• What are the different types of Android APIs and functionality that instant apps can use?

  Google Play Instant functionality complements an existing Android app. This means, it doesn't replace the existing Android app. It uses the same Android APIs, the same project, and the same source code. It restricts some features that may not match users' expectations of an app that isn't installed. For example, an instant app cannot use background services, send background notifications, or access unique device identifiers.

• Can users choose to install the app permanently?

  Developers can allow users to install the app from Google Play by using the showInstallPrompt() method.

• How do permissions work in Google Play Instant?

  Google Play Instant uses the runtime permissions model that was introduced in Android 6.0 (API level 23).

• Which permissions are available to an instant app?

  See the list in the permissions section within the guide about making an app bundle instant-enabled.

• Which SDK version should an instant app target?

  Your instant app's manifest must set targetSdkVersion to 26 or higher.

• Are there any limitations on how an instant app handles network traffic?

  All the network traffic from inside instant apps must use HTTPS. Instant apps doesn't support HTTP.

• How do developers publish instant apps?

  Developers publish their instant apps through the Google Play Console, similar to their existing Android apps. For more information, see Distribute your instant app.

• Is Smart Lock required for instant apps?

  Yes, apps that require users to log in must implement Smart Lock for Passwords on Android.

• Can I implement an instant app without an installable Android app?

  No, you need to have an installable version of your Android app in Google Play.

• Can we use WebPs for views?

  Yes, you should use WebP to format images for views.

• How do instant apps show up in Google web search?

  Instant apps show up the same way as an installable app shows up in the search results. If there is an instant app associated with the URL, the app shows up with an app icon and a label with the text "Instant".

• Can I use Google Play Instant to distribute my game?

  Yes, games are fully supported on Google Play Instant. To get started, learn how to convert an existing game to an instant app.

Project structure, features, and architecture

• Do instant apps and installable apps have separate build.gradle files?

  You need two separate build.gradle files if you build your installable app and instant app from the same Android Studio project.

  • Build your installable app from a module that uses the com.android.application build rules.
  • Build your instant app from a module that uses the com.android.instantapp build rules.

  For more information about how to create an instant app, see the guide on how to Convert a feature module to an instant app.

• Can I build my installable app separately from my instant app?

  The recommended project structure, as discussed in the Convert an app to a base feature module and Convert a feature module to an instant app guides, prioritizes separating functionality into library modules, where the installable app and instant app depend on those library modules. If you follow the recommended project structure, you can build each feature separately from the installable app.

• Is NDK supported on my instant app?

  Yes. NDK is supported on devices running Android 5.0 (API level 21) and higher.

• How do I navigate between activities in an instant app?

  You can navigate between different activities by launching a URL dedicated in a different feature. You need to address activities through a URL. For more information about addressing activities via a URL and implementing app links, see Provide URL access to an instant app.

• Can I use a routing activity in my main app that deals with deep links and calls other activities as needed?

  Instant apps also need to be functionally modular. A central routing activity restricts modularization. Using Android App Links allows the Android framework to do the routing, while enabling more modularization.

• Can I have multiple activities in a single feature?

  You can have multiple activities within a single feature. However, you must be mindful of the 4MB size limit for instant app downloads. Also, each feature needs to have a single activity as its entry point.

• Can I share resources between features?

  Yes, resources in the base feature are available for all the features. Resources contained within a dependent feature is limited to that specific feature.

  You must keep the file-based resources' names distinct between your dependent features and base feature. For example, if your base feature defines a layout in res/layout/feature_layout.xml and a dependent feature defines another layout with the same file name, the instant app might load the layout from the dependent feature when actually the layout from the base feature is expected.

  In addition, all the resources referenced by the manifest of a feature module must be present in the base feature module.

• If there are two features in the app, do they share memory?

  Yes, the features run in the same process and share the application context. As long as they belong to the same instant app, features act similarly to different components of a single app. Components like storage and resources are accessed similarly.

  However, instant apps have some restrictions compared to installable APKs. For more information, see the Google Play Instant policy page.

• Can I have multiple fragments in a view-pager within a single activity?

  Yes, you can have multiple fragments in a single activity and define the fragments relevant to the activity within the feature. Activities must be the primary entry point within a feature. Keep in mind that fragments cannot be associated with a deep link and cannot be launched independently of an activity.

• Should the instant app have a separate launcher icon?

  No, you shouldn't branch your UI. The instant app and the installable app should share the same icon as it is important that both the apps provide the same look-and-feel. Therefore, you should use the same visual elements for both the apps.

• How can I find out if my app is running as an installable app or an instant app?

  Use the isInstantApp() method. The method returns true if the current process is an instant app.

• How can I prompt users to install my app from my instant app?

  Use the showInstallPrompt() method. This shows a prompt to the user to install the regular APK version of the app.

• Do different APKs for features mean different listings in Google Play?

  No, the instant app and the installable app share the same package name and listing.

• Are there any restrictions on how I name features within my instant app?

  Feature modules follow the naming conventions established for Java package names. As an example, you cannot use hyphens in feature names. For more information about Java package naming conventions, see Java documentation.

• How do I transfer data from an instant app to an installed app?

  For devices running Android 8.0 (API level 26) or higher, the instant app's data is transferred automatically when the APK installation begins, if the installed app is configured to use targetSandboxVersion 2.

  For installed apps not configured to use targetSandboxVersion 2, or devices running Android 7.1 (API level 25) or lower, please consider using the Cookie API (Sample) or Storage API (Sample) to transfer the data.

• Is multidex supported for instant apps?

  Multidex is supported for instant apps. If you have an app that satisfies the maximum size requirement but contains more methods than the dex limit of 65,536 methods, you can still enable multidex and publish it as an instant app.

Analytics, Google Play, and deployment

• Can I restrict my instant app to launch in specific countries?

  Instant apps are limited to the countries where the installable app is available. Within those countries, developers can choose countries to target their instant app.

• Do I need to publish an installable app to test my instant app on an alpha track through Google Play?

  To test your instant app's deployment on the internal testing track through Google Play, you must have a draft form of your app's installable version in the Google Play Console. For more information about deploying and testing an instant app, see Distribute your instant app.

App size

Note: For games on Google Play Instant, the download limit is 10 MB. If you're a game developer, follow the guidance in this section, but replace each instance of 4 MB with 10 MB.

• What does the 4MB total download limit mean?

  The size of the instant app (base feature plus any included dependent feature) should be as small as possible. The smaller your app, the easier it is for the users to download. However, once the instant app is running on the user's device, you can download additional data and store it in the internal storage. There is no 4MB hard limit for storing data in the internal storage of the device.

  To calculate the size, unzip the Instant App APK and examine the APK APK files. You can either use the disk size of the APK files or open the APK Analyzer and check the Raw File Size value.

  For an instant app with multiple features, you must add the size of the base feature APK to a single feature APK. The total size of both these APKs must be under 4MB.

• How do density, ABI, or language APKs affect the 4MB limit?

  Feature size is calculated by adding the feature APK size, the base feature APK size, the largest language, screen density, and ABI APK sizes that are associated with the feature. For example, if a feature has three languages, one screen density, and no ABI APKs, the final feature APK size is derived by adding the feature APK size, base feature, the largest language APK, and the one screen density APK.

• Do users need to download the base and dependent feature APKs each time they download the same instant app?

  When users download an instant app, they receive the base feature and the dependent feature. When a second feature or feature APK is requested, the user receives only the feature APK for that specific feature. In such case, the base feature isn't downloaded again.

  The system can clear the cache of instant apps as needed during garbage collection. If the user reboots the phone, the instant apps cache is cleared. This means that users must re-download the base feature.

• When does the 4MB validation occur?

  The validation occurs when you upload your instant app to the production track of the Google Play Console.

App Links, deep linking, and URL handling

• My links don't open in an instant app when they are clicked from some other apps. They open inside an in-app browser instead. Is there a way to ensure that users are taken to an instant app?

  Since App Links are regular URLs, apps can force them to be opened inside an in-app browser. Consider using Firebase Dynamic Links to wrap your URLs and guarantee that links always open in your instant app.

• My main app manifest includes other URLs or other URL domains that I don't support or own. What are the consequences?

  If the domain ownership of a URL isn't verified, the instant app cannot be published.

• My URL is opening the wrong activity. What do I do?

  The selected activity is based directly on your activity's <intent-filter> elements. Check for common mistakes, such as different activities having overlapping "android:pathPrefix" attributes. For example, if one activity defines android:pathPrefix="/recordList" and another defines android:pathPrefix="/record", the behavior can be undefined. Use unambiguous path definitions, such as android:path="/recordList" and android:pathPrefix="/record/". This would allow /recordList to match a scrolling list of all records and /record/123 to match a specific record.

Running instant apps on a device

• Is there a way for users to opt out from Google Play Instant?

  Yes. Users can opt out when they first launch an instant app. They can also opt out by turning off the instant apps from Settings.

• Can two instant apps run in parallel?

  Yes, instant apps can run in parallel and users can switch between them. Only the instant app in the foreground has an icon in the notification shade.

• Can a user kill instant apps process and restart it from Recents or from the device's home screen?

  A user can restart an instant app from Recents or by tapping on the URL that previously launched it.

  The instant app process is killed when the instant app goes in an idle state. However, the internal storage of the app like SQLite DBs and shared preferences remain active. If the device is severely constrained, the instant app might be evicted and its internal storage is deleted. In this unlikely event, you must restore the instant app state from their servers.

• Can instant apps launch other apps that are installed on the user's device?

  Instant apps can launch an installed app by firing an implicit intent. However, it cannot launch most installed apps using an explicit intent. Installed apps can make themselves available to interact with instant apps through explicit intents.

• Which app opens when a user have an older version of the app installed and clicks on an instant app URL with newer features?

  The installed app always takes a preference over an instant app.

• How do users receive new versions of an instant app? Does Google automatically update it on users' devices?

  The latest version of the instant app is served to new users and existing users whose instant apps cache has expired.