在Android 5.1.1上React-native慢，但在旧的5.1上很棒

We have developed a react-native (v0.17.0) application for both iOS and Android. The iOS version is very responsive on physical devices. On Android devices I see a tremendous amount of variability. On Android version 5.1 the app is super responsive. On two separate phones with 5.1.1 (and both phones with much better specs) it is highly unresponsive. The navigation takes at least five seconds, TouchableHighlight buttons sometimes do not register at all. I have of course turned off dev mode but the issue still persists. My issue is that I can't see the degrade in performance on the emulator and this makes it hard to pin down the issue. Has anybody experienced and fixed a similar issue? What would be an advisable way to pinpoint the issue?We have developed a react-native (v0.17.0) appl