I don't want to jump on this bandwagon of "fanboy!" chanting, but it does exasperate me a little some times how little-known Android's "intents" feature is. It is genuinely fantastic, and underused even by Android developers themselves- I never stop being frustrated that I can't make a shortcut directly to Instagram's camera screen.

iOS really has no equivalent, beyond these hard-coded intents for Facebook and Twitter. It's a real shame.