Living in Japan means houses are not very well isolated and many people don't run the heater over night. Consequence: its cold in the morning in the bedroom. 10 to 12 degree Celsius, maybe. The iPhone 5 of my wife react quite erratic in this condition. First it's hard to unlock the screen and if we click on a icon in the top area of the screen actually the phone application might start and randomly select names. Same room condition iPad 1,2,3 and iPhone 4 working perfectly. Question: anybody else seen this ? Would that be a problem with the digitizer in the screen or with the different electrical parameter of the finger ?