It's likely that you came across this news already as it has been widely reported but as of two days ago you are unable to update iOS app screenshots in iTunes Connect without also uploading a new binary. I am linking to Don McAllister's post here as he has investigated a little more and found that Newsstand apps are exempt from this restriction which is good news as you really don't want to have to upload a new app with each issue. If you are wondering why this happened, read the link from Panic which Don links to at the start of his article.
Obviously not directly related to iOS development but this will be an interesting experiment to watch as this is an often requested feature for the App Store. As I have said before, I'm not sure this is the right solution to this problem but it should be fascinating to watch what happens.
Analytics are useless unless you can act on them. Tapstream gives app developers a different kind of analytics, focusing you on user acquisition and engagement. It's quick to setup, simple to digest and starting this month it's available for no cost to indie developers.
New case study on the ImageOptim site reducing the size of the TweetBot package from 33Mb to 16Mb. It would be fantastic if there was a command line version of this so it could be easily integrated into an Xcode build process. I had a quick dig in the bundle and found all of the individual optimiser binaries but couldn't find one that to wrap up the full process like the app does.
Another option for reducing the size of your app bundle by Nick Lockwood. I hadn't heard of JPNG before but this looks really interesting for large background images which still need alpha transparency.
Web based tool to place an iOS screenshot onto a variety of devices in real world situations. The screenshots look slightly out of place as they naturally haven't been adjusted to match the lighting of the original photo but this is a neat little tool nonetheless.
Mike Abdullah with a potentially nasty situation of KVO being fairly broken for weak properties. I think KVO could really do with a bit of love soon with issues like this and what feels like a very outdated syntax against more modern Objectve-C APIs.
Interesting question and subsequent answer by Mervin Johnsingh about the phrasing of error messages. Of course, it depends on the app but I think injecting a bit of humanity into error messages would usually be a positive thing.