The underscore prefix here is referencing the instance variable (synthesized automatically when you declare it as a `@property`), rather than going through the setter method. So if instead you use `self.accountStore = ...`, you'll be ensuring that if you've written a custom setter, it'll be called. The reason the Twitter docs used `_accountStore = ...` is that they were setting the accountStore in `init` - the recommended practice has been to directly access instance variables (not setters) in `init` methods, otherwise use the setter (`self.accountStore = `).

You mentioned not being able to get this to work in `init` - that's likely because you're using a Storyboard, so the framework calls `initWithCoder:` instead of just `init`. See http://stackoverflow.com/questions/8766368/ios5-storyboard-uiviewcontroller-which-init-method-is-called-by-the-storyboard

That's all to say you could (and probably should) set the `entries` and `accountStore` in an `initWithCoder:` method.