iOS App is much larger than Android App

iTunesConnect estimates download size as 77.2mb, installed size will be 158mb.

My iPad settings menu shows the app as 161mb, so really close to the estimated install size.

My Android tablet’s Internal Storage menu shows my app as 79.98mb.

So, my iOS app is DOUBLE the size of my Android app. Anyone know why?

I use compressed texture atlases for all of my textures so there shouldn’t be a huge disparity there between platforms.

Is it possible that the android’s Internal Storage menu is actually showing the compressed app size and it uncompresses the app when it launches or something?

The compression on IOS and Android devices is totally different. Android building in Unity automatically compresses the textures using their method, but iOS builds skip compression. If your textures are compressed as DXT5/DXT1 format (as they should be) on Android, they will “fall down” to a RGB compression on IOS, which is much larger. You can override that compression for IOS, using PRVTC, but you app will never be as small as it is on Android.
OR Set your textures to Advanced and then enable 2 or 4 bit compression (4 bit has better visual quality) and make sure to select the A version of each if the texture has transparency