How to Protect Dynamic Features
What are Dynamic Features?
As of May 2018, Google uses the Android App Bundle (.aab), an upload format that includes all types of code and resources. This allows you to create an .aab file consisting of multiple APK bundles that are optimized for each device or OS store. When uploaded to Google Play, your app bundles are used to generate and serve optimized APK files for each user’s device configuration. As a result, end-users can download only the code and resources they need to run your app, making it easy to reduce the app size.
If your app offers multiple features, some of which may not be available by default to all users (for example, a professional network with stats on who has viewed your profile or features that are only relevant to recruiters), you can set these features (modules) as dynamic features.
In doing so, you can customize how and when different features of your app are downloaded onto devices running Android 5.0 (API level 21) or higher. This allows you to reduce the initial app size by distributing a basic app file that contains only mandatory components. Users can download and install this basic “thin” app and later download the non-mandatory modules as needed. Dynamic features can also be used to exclude features that are only supported by certain devices, such as facial recognition.
Why Should Developers Protect Dynamic Feature Modules?
Dynamic feature modules are organized just like regular app modules: they provide their own code, resources, and assets in the directories you would expect. This means that for all the benefits of using dynamic features in terms of customization ability and app size reduction if these modules are not protected, they can be compromised by hackers and other malicious actors.
How does Appdome Protect Dynamic Features?
Dynamic features support is a separate license provided by Appdome. If you upload an app with dynamic features that does not have a Dynamic Features Support license, Appdome will identify that your app has dynamic features by displaying a disabled Dynamic Features icon in the upload screen, along with a notification that the requested Dynamic Features Support license is missing.
Incompatibility Between Dynamic Features and Universal APKs
Generating a universal APK is not supported on the Appdome platform for .aab apps with dynamic features.
A Universal APK is a single app file that contains all the code and resources needed for every possible device configuration, including different screen sizes, CPU types, languages, and features, which makes it a large file. When your app uses dynamic features — optional parts of the app that users download only when needed — creating a universal APK introduces several problems:
- It bundles all dynamic features into the main app file. This means the optional features are no longer optional — they are installed upfront with the rest of the app.
- It disables Google Play’s dynamic delivery system. This removes the benefits of smaller downloads and modular updates.
- It defeats the purpose of keeping the app lightweight and flexible by downloading only what the user needs.
Because of this, Appdome does not support downloading a universal APK for apps that use dynamic features. This limitation applies to all apps, including those built with Unity. The restriction is not caused by Unity itself, but by the technical conflict between Dynamic Features and the nature of a universal APK.
If you proceed with the build process without upgrading your account, the lack of a Dynamic Features license will also be indicated in the app list menu on the left.
If your uploaded app includes a license for dynamic features support, the license is indicated by a Dynamic Features icon that is enabled both on the upload screen and on the app list menu.
Related Articles:
- How to Protect Unity Code in Android and iOS Unity Apps
- How to Block Lucky Patcher & Patching Tools in Android Apps
- How to Prevent Static App Patching in Android Apps
How Do I Learn More?
If you have any questions, please send them our way at support.appdome.com or via the chat window on the Appdome platform.
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