All fonts are placed in the font/ folder(roboto-bold.xml, medium, and regular). On some devices(Android 5 and 6) the app crashes on launch, here is Stack trace from the Crashlytic:
Fatal Exception: java.lang.NullPointerException: Attempt to invoke virtual method 'boolean c.h.m.e$e.a()' on a null object reference
at androidx.core.provider.CallbackWithHandler.onTypefaceResult(CallbackWithHandler.java:80)
at androidx.core.provider.FontRequestWorker$2.accept(FontRequestWorker.java:174)
at androidx.core.provider.FontRequestWorker$2.accept(FontRequestWorker.java:171)
at androidx.core.provider.FontRequestWorker$4.accept(FontRequestWorker.java:212)
at androidx.core.provider.FontRequestWorker$4.accept(FontRequestWorker.java:200)
at androidx.core.provider.RequestExecutor$ReplyRunnable$1.run(RequestExecutor.java:154)
at android.os.Handler.handleCallback(Handler.java:815)
at android.os.Handler.dispatchMessage(Handler.java:104)
at android.os.Looper.loop(Looper.java:194)
at android.app.ActivityThread.main(ActivityThread.java:5637)
at java.lang.reflect.Method.invoke(Method.java)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:959)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:754)