Report a startup crash on android.

Hey Fellas. Here to ask for some tips . . . I'm developing an android game I am using Unity 5.2.2. Game works fine in Editor and on majority of android devices however, it crashes on some other devices ( Samsung S 6, Sony Xperia U, Samsung Galaxy Ace and some others ... ) right away after splash screen is shown. I've been looking for a way to fix it. I did not find any generic solution for it, since the issue is caused under numerous conditions, like it might be because of the version of the Unity I am using, or the way I coded the game, etc. Therefor I think, the only solution is to get online reports from devices that experience the startup crash. I checked and found some plugins that are able to report crashes, but for crashes that happen on playtime, like Crashlytics.

Thing is, I am looking for a thing that can report the startup crash. are there any suggestions ? also I am open to suggestions that can help me fix the startup crash , which is above appreciable.