Snippet: Reversed Polarity ☍

It looks like that some of the early Smart Covers and many third-party cases aren’t working to activate the sleep/wake function on the third-generation iPad, due to Apple changing the magnetic sensor. The new one seems to actually care about polarity (unlike the iPad 2) and many cases are opposite:

I’ve learned why Apple decided to use a polarity sensitive switch in the new iPad 3. Some iPad 2 customers were having issues with their iPads entering sleep mode when they flipped Apple’s Smart Cover around flat behind their iPad 2. Since the iPad 2’s sleep/wake sensor wasn’t polarity specific, it could sometimes be triggered from the magnet being positioned at the rear of the iPad. By changing to a sensor that requires the correct polarity, the problem is eliminated.

Fortunately you can exchange your Smart Cover for a shiny new one at an Apple Store.