IOS App bigger than Android app

Hello, I am currently developing an app ( an arcade game ) with Unity standard and I want to release it on iOS and Android. It is almost finished , but I have a problem : the game on Android weights 48 MB against 487 MB on IOS.

The editor log says : "Complete size 60 MB 100.0%" but on IOS the app weights 487 MB. The compression format of my textures is : RGBA Compressed PVRTC 4 bits.

Do you know how to reduce the size of my app ?

Thanks