Based on Google's App Engine cost structure where CPU is more costly than bandwidth, is it beneficial to enable gzip compression to your iOS app? Has anyone enabled gzip and seen the real-word cost savings (or cost increase!)?
Background: Our app will primarily serve text content to iOS. iOS supports gzip compression, but it must be turned on in the client by passing the accept-encoding and user-agent headers per: https://developers.google.com/appengine/kb/general#compression
However if gzipped content is sent, iOS will automagically decode it: NSURLConnection/NSURLRequest gzip support
Since we write our iOS app, it's up to us whether to use compression or not. In my past life, the significant bandwidth savings vs. minor CPU usage increase were easily worthwhile. Looking at the CPU vs. Bandwidth costs in GAE, it's not so clear. It could actually cost us money to enable compression.
So has anyone experimented with their iOS app and seen if gzip support saves money? Our app isn't live yet, so I can only do very fudgy cost comparisons in dev, which unfortunately make compression appear to cost MORE money.