How I handle the performances on different devices is a settings menu where the player can set the animations to On/Off, also the background scrolling sky can stopped. Also have the clear background turned off because I have a background covering. That was the biggest improvement that I have done. Amazing differences in the fps since turning that one setting to off.
Also, play around with the "Compare two values" and have it compare the "fps" to a number, and if the number drops below your threshold that you set, have it then set the animation speeds, and such.
Also, you can mimick a resolution change by setting the canvas size to another resolution by touching/clicking a sprite/button. See image that I am posting. by clicking/touching the sprite8 on my layout, it would set my resolution to 100x200[attachment=0:2ipmrcvy][/attachment:2ipmrcvy] I hope this helps!