Although you saved this app to your storage card, there may be some files that were loaded to your device, and possibly some registry changes made. You may have to load a clean up program (which is something you should have anyway), such as MemMaid or SKTools, to properly uninstall. MemMaid can be found at
www.dinarsoft.com and SKTools @
www.s-k-tools.com. They're not free, but have a trial period.