Most of Warzone's storage happens on the Warzone server. For example, all multi-player games, chat, and tournaments are stored completely on the server and only bare minimum of information is transmitted to player's computers.
However, there are some things that get stored on the client. For example, saved single-player games, whether or not sounds are enabled, and orders you've entered into a game but not yet committed.
In the case of the web-based version, these are stored in HTML's local storage system. In the mobile client, these are stored on your device's local filesystem.
 Clearing Local Storage storage
Sometimes your local storage repository can become corrupted which can cause functionality in the game to stop working. If this happens, you can clear your storage. Doing this won't interrupt any multi-player games you are in, but you will lose any single-player games saved in that browser.
To clear your storage, visit https://www.warzone.com/Test/LocalStorage and click Clear.
 Clearing Android's Storage
- Tap Home
- Tap Settings
- Tap Applications
- Tap Manage Applications
- Tap Warzone
- Tap Clear Data, OK
- Also tap Force Stop to stop it if it's running
- Tap Home and re-launch Warzone