3gs factory unlocked - can not use Cydia

[mktmkr]

Hello and sorry if this was covered somewhere...

I have a 3GS factory unlocked... 3.1.2 Used blackra1n to jailbreak/install Cydia. Cydia installs and updates fine, but after I install any application (I tried about 5) it gets to the part when it needs to Reboot, the phone becomes inoperable and has to be restored via Itunes. I need to run a few apps from Cydia and this is really killing me. Any advice would be appreciated!!!

 

[Applejuiced]

Its called a tethered jailbreak.

 

[thelatinist]

You have a tethered jailbreak. You do not have to restore, you just have to run blackra1n again each time your phone reboots.