I think this problem is on all games. The one minute you get a hundred fps in overwatch, the next you get 40

So I may have figured out the issue for anyone else who may be having the same problem. My phone is fully capable of playing at 60fps, but it seems that every time I open the app, I get a 40 fps or 60 fps capped "version" of the game, in which all of my subsequent games are set at that fps limit until I close the app.

So I have just been restarting the app until I get the 60 fps limit. I can actually "feel" whether I am getting a high framerate in the lobby, while scrolling through my weapons and/or simply sliding the view of my mechs.

This is simply a bandaid fix, but at least it works :) Perhaps Plarium can sort out the technical issues bit by bit in the future. 

The device might be overloaded with other background processes.  You phone is capable of running 60fps games but if another process is requiring resources it will throttle your phone to accomidate the application.  Sometimes I will run my phone on Airplane mode when gaming on Wifi to elimate all other processes running in the background.

Otherwise, the recommended fix is what you are already doing which is restart the application.

Thank you for the reply. I will try airplane mode. Oddly enough, switching to a 30fps limit has made my game much smoother than having it at 60 throttled to 40.