A trick to get more storage space on your iPhone has been circulating around the Internet today — but you have to have less than a gig of available space left on your phone to make it work.

Redditor eavesdroppingyou posted a tactic for clearing up extra space that involves renting a movie from iTunes (don't worry, it won't charge you). Eavesdroppingyou suggests picking a long movie like The Lord of the Rings: The Two Towers, because the trick requires that the movie's file size exceeds the amount of storage left on your phone.

After you hit the Rent button on a movie, a dialog box will come up, which will prompt you to hit OK or Settings. Hit Settings.

The dialog box that appears when trying to rent a movie that exceeds your storage size. Image: mashable

Your phone will take you to the Settings menu. If you take a look at General > Storage & iCloud Usage, you'll see that your phone's available storage space has probably gone up. My iPhone 5S with iOS 9.3 started at 890MB and jumped up to 1.6GB available.

If you hit your home button, you can see your iPhone working through different apps, graying them out and replacing their names with "Cleaning..." This likely means that your phone is removing a bunch of unused data and things like cookies, caches and histories. Your iPhone might automatically do this when storage space gets very low, but this is a great way to force the process to happen.

When I tried this, my phone went for Safari first, and also cleaned my Twitter, Snapchat and Imgur apps.

In the two images, you can see the iPhone "cleaning" the Safari app and then the Twitter app. Image: Mashable

The Reddit post suggested renting the movie multiple times to free up more space, and it works. After three more cleanings, my iPhone had 3.9GB of available storage, and I didn't even have to remove any apps, photos or podcasts.

In just five minutes, attempting to rent a movie a few times brought this iPhone from 890MB of available storage to 3.9GB. Image: Mashable

Try this out for yourself to get your phone to do some cleaning for you — it could save you from deleting some items you'd rather not give up.

Image: mashable Composite

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