Q: How can I completely delete a downloaded movie that had an error in downloading? It is using up 3.5GB on my iPad and I can't even play it.

How to delete content you’ve downloaded from the iTunes Store, App Store, iBooks Store, or Mac App Store

http://support.apple.com/kb/HT5772

iPhone, iPad, and iPod: Understanding capacity

http://support.apple.com/kb/ht1867

How much space is used by your Other? You may be able to reduce.

How Do I Get Rid Of The “Other” Data Stored On My iPad Or iPhone?

http://tinyurl.com/85w6xwn

How to Remove “Other” Data from iPhone, iPad and iPod Touch

http://www.igeeksblog.com/how-to-remove-other-data-from-iphone/

With an iOS device, the “Other” space in iTunes is used to store things like documents, settings, caches, and a few other important items. If you sync lots of documents to apps like GoodReader, DropCopy, or anything else that reads external files, your storage use can skyrocket. With iOS 5/6/7, you can see exactly which applications are taking up the most space. Just head to Settings > General > Usage, and tap the button labeled Show All Apps. The storage section will show you the app and how much storage space it is taking up. Tap on the app name to get a description of the additional storage space being used by the app’s documents and data. You can remove the storage-hogging application and all of its data directly from this screen, or manually remove the data by opening the app. Some applications, especially those designed by Apple, will allow you to remove stored data by swiping from left to right on the item to reveal a Delete button.

What is “Other” and What Can I Do About It?

https://discussions.apple.com/docs/DOC-5142

iPhone or iPad Ran Out of Storage Space? Here’s How to Make Space Available Quickly

http://osxdaily.com/2012/06/02/iphone-ipad-ran-out-of-available-storage-space-ho w-to-fix-quick/

6 Tips to Free Up Tons of Storage Space on iPad, iPhone, and iPod Touch

http://osxdaily.com/2012/04/24/6-tips-free-up-storage-space-ipad-iphone-ipod-tou ch/

Also,

How to Clear Message/iMessage Cache on iPhone & iPad And Reclaim Lots of Free Space

http://www.igeeksblog.com/how-to-clear-message-imessage-cache-on-iphone-ipad/

What is Stored in iCloud and What is Not

https://sites.google.com/site/appleclubfhs/support/advice-and-articles/what-is-s tored-in-icloud

 Cheers, Tom