This is particularly important for secondhand or other mobile devices that you might buy or receive as a gift, and want to activate on the wireless network that meets your needs -- even if it isn't the one on which the device was first activated.

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T-Mobile had one low end WP7 device that we considered for our daughter (She choose something else).

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We tested the Mobile with an iPhone 4 and a touch, and, while the fit wasn't perfect with either device, neither one fell out.

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