How to Free Up Space on the Kindle
When you begin to run out of space on your Kindle tablet or e-reader, the first thing to consider is deleting any e-books, videos, songs or apps you're not using. If you purchased these items from the Kindle Store or the Amazon Appstore, you can delete them from your Kindle and still access them at any time from the Amazon cloud. If this doesn't solve your problem, and you have one of the Kindle Fire tablets, you can also free up space by clearing your application cache and deleting junk files.
1 Kindle Fire Cleanup
When you use an app on your Kindle Fire, Fire HD or Fire HDX, the app stores temporary files in your tablet's memory. Many apps are good about cleaning up after themselves, but others allow the cache file to build up over time, eventually causing you to run low on space. You can clear the cache for each app manually from the Applications section of your tablet's settings. Simply tap the name of an app, tap "Storage," and then tap "Clear Data." You can also install one of several cleaning tool apps that do the job for you, such as Clean Master, Clean Kindle or Clean. These apps also clean up any junk files they find on your Kindle.