Or PowerVR texture compression, which according to Anandtech is the canonical method for iOS development:
"Because Appleās SoCs have always used GPUs from the same vendor, certain vendor-specific features like PowerVR Texture Compress (PVRTC) are widely used in iOS app development"
"Because Appleās SoCs have always used GPUs from the same vendor, certain vendor-specific features like PowerVR Texture Compress (PVRTC) are widely used in iOS app development"
[0] http://www.anandtech.com/show/11243/apple-developing-custom-...