PVRTC or ASTC for AppStore?

Can somebody please provide information?

If i choose PVRTC and ASTC the package is extremely huge for distribution… if i only pick PVRTC will A8+ devices support it?

Thank you!

see here: PVRTC vs ASTC texture compression on an iOS device
They use Unity but it also applies to Unreal.

So backwards compatible with pvrtc is possible? Don’t care about that much for the image quality if am to get x2 the app size