We spent quite some time trying to figure out why we were getting performance hits and we were having frame rates as low as 5-10 fps on android devices. Since we’re making a quite simple 2D casual game the frame rate should be high all the time. After a few days of performance fixing and the frame rate still being low we decided to wait and see if a patch of unity would fix the problem…
It turns out Unity 5.3 had serious issues with dynamic batching which apparently affected SpriterRenderer.Renderer and made the frame rate go way down.
The resolution came the 23rd of december with 5.3.1p1.
Lesson learned? Wait until the first patch of a major update or have a backup plan 
Thanks for sharing this! After a day of solving bizarre unity specific issues I was ready to set fire to something…..