Cydia updates caused a problem. When I went to respring the ipad it got stuck on the apple logo and the spinni9ng wheel. Tried to turn it off many times but no luck. Did a search on the forums and read about how to reboot. Hold sleep/wake button and home button together until the apple logo appeared. Tried it. held for about 10 seconds and it changed from spinning apple to just apple logo. Waited 3 or 4 mins and then it sprang back into life. Phew!!!! Not sure what the upgrades was. I had 7 to do when I turned cydia on. Just thought I would let any one know about the reboot if you experiance a similar problem.