I am developing a 2D game for Android with Unity.

At the first stage of development the file size was 18 MB with almost nothing in it. Then it grew up to 65 MB and I've managed to reduce it to 45 MB using the checklist below. But I think it can be smaller yet.

The things I have tried so far:

1. Removing duplicate or unused assets
2. Reducing sprite sizes
3. Reducing SFX sample rate and bit rate
4. Using Texture Compression for sprites
5. Removing external assemblies

Is there anything else that I should add to the checklist?