App Bundle, split APKs and Multidex

Your app might observe crashes due to UnsatisfiedLinkError or LinkageError (since ObjectBox 2.3.4) on some devices. This has mainly two reasons: If your app uses the App Bundle format, the legacy split APK feature or Multidex the native library can't be found. Or if your minimum SDK is below API 23 (Marshmallow), there are known bugs in Android's native library loading code.

Let us know if you have more info on this in GitHub issue 605.

App Bundle and split APKs

When using an App Bundle or split APKs Google Play only delivers the split APKs required for each user's device configuration, including its architecture (ABI). If users bypass Google Play to install your app ("sideloading") they might not install all of the required split APKs. If the split APK containing the ObjectBox native library required for the device ABI is missing, your app will crash with LinkageError when building BoxStore.

Update: With the Play Core library Google now provides an official, easy solution to detect if an app is incorrectly installed and direct the user to fix the problem (e.g. to reinstall the app from Google Play). We recommend using the Play Core library instead of the below workarounds. See how we updated our example app to use the Play Core detection.

If you do not want to use the Play Core library, there are two alternatives:

Alternative: turn off splitting by ABI

The simplest solution is to always include native libraries for all supported ABIs. However, this will increase the download size of your app for all users.

android {
bundle {
abi {
// This property is set to true by default.
enableSplit = false

Source: Android Developers

Alternative: Catch exception and inform users

You can guard the MyObjectBox build call and for example display an activity with an info message (e.g. direct users to reinstall the app from Google Play, send you an error report, ...):

// guard the build call and set some flag (here setting the boxStore field null)
try {
boxStore = MyObjectBox.builder()
} catch (LinkageError e) {
boxStore = null;
Log.e(App.TAG, "Failed to load ObjectBox: " + e.getMessage());
// then for example in the main activity check the flag in onCreate and
// direct to an info/error message without the app crashing:
if (ObjectBox.get() == null) {
startActivity(new Intent(this, ErrorActivity.class));

As an example see how we added this to our Android app example.

Buggy devices

On some devices and if your minimum SDK is below API 23 (Marshmallow), loading the native library may fail due to bugs. To counter this ObjectBox includes support for the ReLinker tool which will try to extract the native library manually if loading it normally fails.

To set this up add ReLinker to your dependencies:

implementation 'com.getkeepsafe.relinker:relinker:1.3.1'

ObjectBox is calling ReLinker via reflection. If you are using ProGuard or Multidex, make sure to add keep rules so that ReLinker code is not stripped from the final app or is not in the primary dex file.

For ProGuard add this line:

-keep class com.getkeepsafe.relinker.** { *; }

For Multidex add a multiDexKeepProguard file to your build file:

android {
buildTypes {
release {
multiDexKeepProguard file('')

And in the file add the same rule as above:

-keep class com.getkeepsafe.relinker.** { *; }

Multidex supports two file formats to keep files. We are using the ProGuard format (multiDexKeepProguard property). You can also use the multiDexKeepFile property, but make sure to adapt the rule above to that format.

Enable ReLinker debug log

To enable debug logs for ReLinker you can pass a custom ReLinkerInstance when building BoxStore:

boxStore = MyObjectBox.builder()
.androidReLinker(ReLinker.log(new ReLinker.Logger() {
public void log(String message) { Log.d(TAG, message); }