iOS8 comes with quite a handful of new features. One of them makes it easier for you to entice a user to share your lovely app.
As you know, when accessing Contacts or Location your app has to ask the user for permission. Apple has now added a feature that allows your app to access just one single contact. The great thing: the app does not need to ask for a permission. Try this mechanism to build up trust more easily. Additionally, the app can also look for just a subset of a contact's properties, e.g. just the phone number. The iOS Contacts API comes with another cool addition: iOS can filter the address book for e.g. email addresses that end with @apple.com. This could make it pretty simple and fast to invite co-workers. Beside all those neat additions, your app now has to ask for permission when accessing the camera.