Texture format for 2D Android Game

Hello every one
I’m working on Android game that have a lot of objects with same shape & different text and color on them.


For now I’m using .png but I think the .png file is big!
After that issue I decide to use Shader that have { one alpha layer (all of objects have same Alpha) and a .jpg texture } but I get confused and don’t know what is good for my Android game. TIFF , PNG , JPG or what?
Can you help me which format is good to have smal size and fast game?

Unity does not use the source file for anything aside from importing. The only thing that matters is the texture settings in Unity. But don’t use JPG since that’s lossy and you gain nothing (since, as I mentioned, it’s not used after importing). Unity - Manual: Texture Import Settings