Batch optimization of PNGs for iphone/ipad display as xcode does

Question

I\'m working on a magazine viewer for ipad and I\'m struggling with the performance.

I figured out that the most expensive part of displaying the pngs is the loading

Answer 1

The best results I know of are achieved with ImageOptim, which I use myself for PNGs that are not deployed via Xcode. It uses pngcrush and some other PNG optimization tools to achieve best compression. As far as I know, it doesn't employ alpha premultiplication and byte swapping though. ImageOptim also has a nice GUI with drag-and-drop support and can crush multiple files simultaneously.