OutOfMemoryError in Android Tests

I have a lot of test for Android application and when I run them separately It is OK. But if I start All tests, testing falls with OutOfMemoryError after 10-15 minutes.

I use Robotium test system and Genymotion emulator.

com.my.package.AnyTest:INSTRUMENTATION_RESULT: shortMsg=java.lang.OutOfMemoryError

INSTRUMENTATION_RESULT: longMsg=java.lang.OutOfMemoryError

INSTRUMENTATION_CODE: 0