Asus have recently announced their Padphone, a tablet device that lets a user seamlessly switch between a tablet and a smartphone depending on their need of the screen size.
As the padfone makes use of the same SIM card for 3G network connectivity and single storage pool for data storing on both devices, users can make a smooth transition of applications from pad to phone. Moreover, the pad also doubles up as a charging device for the smartphone.
The following videos are more explanatory.
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