iOS: how to reduce size of large PNG files

Question

I\'m currently optimizing my iOS app for the new iPad. Unfortunately by adding launch images for the iPad retina display the size of my ipa grows from 1.2MB to

Answer 1

Ive struggled with this too, unfortunately not much can be done.

In an effort to dramatically increase drawing performance of iOS apps, Xcode re-compresses PNG files as it builds. It premultiplies the alpha channel and byte swaps the red, green and blue channels to be sequenced blue, green and red. The result is optimised for iOS’s purpose, but as a side effect, ImageOptim’s work gets undone…

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