In short The solution is "do not yse OTA update, update using iTunes, connect, press shift and click update and select beta 2 firmware file, and mive forward. It will update without geting stuck on activation screen.
It really works. Solution for "how to check balance (USSD CODES) on any iPhone running ios 7 unlocked with any gevey or goguo or Rsim. It really works ! I tested on iPhone 5. Thank you ! U need yo be jailbroken .
Be careful. It asks you for Activation. U need to be developer. I was stuck in activation screen. Then i registered my udid over ebay, for 5$. Now i'm on iOS 7.1 beta 2 iPhone 5. Also using GOGUO gevey unlock (similer to Rsim) : working perfect. Omg this beta 2 is super faster. Much much better battery performance. Just LOVING IT. Apple is improving ! (Y) ♥️ 🙊 Anybody has any question ? Ask.