Zevra is a weak engine written by Oleg Smirnov. Its playing strength in Rapidroid scale should be around 1650 ELO. Unfortunately, i had to stop introducing Zevra because same hanging on move behaviour as it was the case with GreKo 2016 and Protector 1.90.AP happened today.
About 50% of the games played with black by Zevra needs to be replayed after a division. I hope Alexei and Aprijal can find the trick behind this problem with Chess for Android.
However, you can always try Zevra with Droidfish or for human vs machine games in CfA.
In case of trouble downloading from your PC, use your mobile device or refer to THIS POST.