When I had my last Android phone (KitKat 4.4), best tip for increasing UI snappiness was reducing (or disabling) system animations. I still miss this option on most modern OSes, shells, apps, and websites.

It's very rare that animation is not blocking further user actions. No surprise animations are tricky to program - they're very async in nature. Designing animation system that doesn't leak into the rest of application logic code is a no simple feat.