What is semi-tethered iPhone jailbreaking?
You may have heard of tethered vs. untethered iPhone jailbreaking solutions. For those who are stuck with a device running iOS 5 that requires a tethered boot there's now a partial solution to make sure you don't end up with a useless iPhone until you return to your computer.
Currently, if your tethered jailbroken iPhone needs rebooting away from your computer the device is unusable and hangs at the Apple logo. To solve this problem, BigBoss has developed the SemiTether package.
The package can be found in a special BigBoss repository (see a complete tutorial on how to semi-tether your iPhone iOS 5 jailbreak). After the semi-tether is installed you will be protected from having a useless iPhone until you can get to your computer and reboot tethered. Currently the stock web browser (Safari) and the Mail app will not work in a semi-tethered state. No jailbreak apps or tweaks (including Cydia) will run until you reboot tethered.
Still, using the semi-tethered package and having these limitations temporarily is better than having an iPhone that won't work at all.