iOS 7 beta 1 Unlock with Ultrasn0w and Gevey Sim
But you need to know that iPhone baseband will be updated as well. And such unlock tools like Gevey Sim (or other turbo Sim) and Ultrasn0w will not work on iPhone 4, 4S after modem firmware update. Simply because these unlocks depend only on the baseband version, not on iOS firmware. You can checkout iOS 7 beta 1 baseband versions and find that there are no tools to unlock them except paid factory unlock.
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Unlock iPhone iOS 7 beta Using SAM
You are more lucky with SAM unlock in case you have saved Activation tickets. But I do not know if it is possible to jailbreak iOS 7 beta 1 iPhone 4 with current Redsn0w or Sn0wbreeze . So you better stay tuned because I will update this post soon with the link or with the additional info about it. The whole process is impossible without jailbreak as well as for using Gevey or Ultrasn0w. If you don't know how to perform this unlock you can follow guide for SAM on iOS 6.1.3 iPhone. The process will be the same as usual.
Factory Unlock iPhone Running iOS 7 beta 1
As you see, the only way is paid unlock. What can you do next if your baseband doesn't support previous unofficial unlocking tools? Only factory unlock will help you. Get it and try all others beta version and then the public version of iOS 7 on permanently unlocked iPhone. This is the easiest and 100% working method if you know the carrier (mobile operator) to which your iPhone is locked and your device is activated. If you don't know the carrier you can always use iPhone network checker and find it out before looking for the package you need.
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LetsUnlock iCloud Tool is ready to remove Find My and unlock your passcode disable device running on iOS 13.x.x in one click!
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