It got stuck in a boot loop the second my device was updated to lollipop (Nexus 4), same thing on my friends Nexus 5.
I spent hours changing java versions and messing about with the Android SDK and then finally I decided to downgrade unity to 4.6.0f3 which I still had on my PC. It all works now. Not quite sure what caused this.
It’s the same thing for all of my apps.