April left a comment on the post about cleaning up your Kindle Fire: “The internal storage is all clear, yay! BUT… the APPLICATION STORAGE is still nearly full. I have looked every place I can think of with the file explorer and cannot find where this is stored. Please help!”
I suggest the following: Try checking the data usage for each individual app by going to Settings–>Applications–>Installed Applications–>[app name here]. When you tap on the listing, you will see all the data accumulated for that app. You have the choice to clear it if you want. Remember, some of the data may be critical for ongoing use of the app, so clear with care! You can also clear the Cache from this screen.
More on cleaning up your Kindle Fire here…