Microsoft is doubling the amount of free storage iPhone users get with OneDrive. "We think you’ll appreciate having more free storage while setting up your iPhone 6 or upgrading to iOS 8. It’s a limited time offer, so act fast and download OneDrive for iOS," said Douglas Pearce, Group Program Manager, OneDrive.

All you have to do is sign up for OneDrive and activate the auto upload feature for your camera roll sometime between now and the end of September, and you will get 30 GB of free OneDrive storage moving forward (15 GB base and 15 GB camera roll bonus).

This also applies to anyone who already uses the OneDrive camera roll on Windows Phone (Windows Phone Store), Android (Google Play Store) and Windows (Download) – you’ll see your storage go up as well. Same for any existing iPhone users who backup their photos to OneDrive.

When you are setting up your new phone with OneDrive, all your photos and videos will be available without taking up space on your device. You can also can get more done with the combined power of OneDrive, Office Mobile, and OneNote.