My iPhone 4 is eating my storage?

My iPhone 4 is eating my storage! I only have 1.3 GB of photos and that's what taking up the most space that I know of. I plugged my phone into the computer and it says that there are over 4 GB used by "other". I don't know what it is or how to fix it! I delete all my messages and emails and anything I can but I always have 0 MB of storAge. I can't even take pictures or access some apps cuz I don't have any storage. How can I fix this?

Check your web cache, could be left over videos and images from the web. Easy to clear in the Settings screen.

You need to get a higher authority, remove unused software.