I'm not a big fan of singletons, especially when they are used as they often are - as glorified globals. That being said, it occasionally makes sense to have some kind of shared instance of an object; not a true singleton that strictly prevents more than one allocation, but a convenient default instance.
Reading Marcus Zarra's own style guide, I thought I'd write a post outlining my own conventions.
Today marks the beginning of the Apple WWDC 2011. I'm not normally one for attempting predictions, especially not on my blog, so this won't be another predictions post. If you want one of those, then Gruber is your man.
Twitter for iPhone (formerly Tweetie) has long been one of my favourite iOS Twitter clients (#dickbar fiasco not withstanding) and has some innovative UI features, particularly it's much imitated "pull-to-refresh" behaviour.
Until recently, deploying ad-hoc builds of iOS apps to beta testers was a pain. You needed to maintain a list of testers, obtain their UUIDs, manage provisioning profiles and compile and distribute the builds (and provisioning profiles) yourself.