Evidence of another version of the iPad, this one coded as “iPad2, 4”, have been unearthed in the iOS 5.1 beta firmware by 9to5Mac.  There is no evidence of exactly what form this model might take, although it is likely that it refers to a version of the iPad that works on Sprint networks, or a model that works on both GSM and CDMA networks.

While it is possible that Apple could be planning on introducing a Sprint-specific model of the iPad 2, there is also a chance that it is looking for a way to slim down its SKU’s even further by introducing the dual-mode CDMA/GSM Qualcomm chip that is used in the iPhone 4S, to the iPad.

This would enable it to cut down its offered models of iPad significantly, producing 6 models (two colors and three capacities) instead of 18 different models of iPad for CDMA and GSM carriers.

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