Atlas optimization for IOS and Android in UNITY?

Question

Android

Hello. In general, I encountered a strong decrease in the quality of atlases when going to these devices.
2 types of atlases are used:
1) Atlas which are assembled by Unity - Create - Sprite Atlas

Which is the best mod compressor to use?


2) Atlas that is built using SPINE 2D, and then imported into the project?
What is the best compressor mod to use?


thanks for the help