If you have iOS 8, you have the ability to share all your iTunes purchases with other members of your household with Family Sharing. After you've setup and enabled Family Sharing all you've got to do is invite people. And if you're on the receiving end, you've just got to accept the invitation to get started.
How to accept a Family Sharing invitation on iPhone and iPad with iOS 8
- When you receive a Family Sharing invitation, it should show up on your Lock screen.
- Slide your finger across it to open it.
- Tap on Accept at the bottom of the screen.
- Choose whether or not you'd like to share your location with others in the Family Sharing group.
That's it! Alternately, if you've dismissed the notification, you can go into Settings > iCloud > Family Sharing and there should be a pending invite waiting for you to accept. If you ever decide to change location sharing options, you can turn that on or off in iCloud Settings as well.