While Returning back after rating the apps it crash

Project Information

Repository: https://github.com/iPoli/iPoli-android

Expected behavior

it expected that user should be able to continue back in app when click on Encourge us and going to playstore user should able to access on the app instead of crash app.

Actual behavior

After rate the app when user again entering the app,then app has crashed.

How to reproduce

download the app

open it

.Rate the app

.Click on back button & note the bug.

• Browser/App version: MyPoli v2.1.1

• Operating system: android 6.0.1

Recording Of The Bug