Huge difference in memory size from Android to Iphone(IOS)

Hi everyone,

I am making a 2d game with unity with a tone of sharp 2d graphics. For Android we had the texture compression set to Automatic True Color. When making an Android build the .apk is about 30mb and the game takes about 30-50mb in RAM while running.

Now taking that same game and switching to Iphone(IOS) with the texture compression set to RGBA32 we build the game and get an Iphone game install that is around 220mb! And takes just as much space in RAM on the Iphone.(around 215mb)

We tried switching to RGBA16 texture compression for the Iphone, which cuts everything in half. (around 120mb) But I just don't understand how the Android version takes so much less space on disk and in memory with the same sharp graphics?

We don't think we can use PVRTC because everytime we do it just looks way to bad and adds too many artifacts. Also I thought automatic true color for Android and RGBA32 for Iphone were about the same texture compression and unity seems to suggest the same when showing the file size.

The only thing I can really think of is Android has a built in way of doing much better dynamic loading of textures and has some sort of auto compression? I really just don't understand this one. You can put the game running on a Samsung Galaxy s2(40mb RAM) and an Iphone (210mb RAM) side by side and they look identical!

Thanks anyone for the help.

-Kurt