BigBoss has released a semi-tethered jailbreak for iOS5, which will allow users to reboot their jailbroken device into a mostly-usable state without needing to re-run redsn0w. There are a few limitations, but it’s certainly better than being stuck at the Apple logo if you forget to juice up your device.
You’ll need to be jailbroken with redsn0w prior to installing, but if you’re ready to proceed, the package is available from Cydia at the http://thebigboss.org/semitether repo. Keep in mind that this is very beta, so make sure to read up before installing.
Here is a summary of what you can and cannot do when in semi-tethered reboot state. Remember, this is only when your device crashed and rebooted on the road and before you got back to your computer to “just boot”. It is better than being stuck in apple logo:
1) Can use phone, sms (text messages)
2) Can use every other stock app on iphone.
3) Cannot use mobile safari
4) Can use other appstore web browsers such as atomic web browser
5) Cannot use mail app. You could install a gmail app from appstore or such instead.
6) You cannot use any jailbreak tweak, app, cydia until you boot tethered.
7) While in the semitether booted state, you should not add a jailbreak ios5 notification such as sbsettings to notifications during this state or your device will be stuck in a respring loop until you get home to “boot tethered”.