Is there any need to update again on ios 7 when i have updated it one month ago using ios 7 beta version? I update my iphone 4 on ios 7 beta version one month ago. Is there any need to download ios 7 full version and update again? However in settings (software update tab) it is showed that your software is up to date.
You should update your phone to the Gold Master (GM) or restore your phone back to iOS 6 and then update to iOS7 using the public version.

If you continue to use the beta, you will not have all the latest updates/fixes from GM and may also run into issues later.