Hey, morrisbulldog! Sorry to say I'm not able to shed any light on this. I can't recall any of our users describing using such a piece of equipment, at least not off of the top of my mind! I will say that generally speaking you'll want to make sure anything you purchase is advertised by the MFR as being compatible with whatever phone you're using, and supports all of the T-Mobile network! It's also worth mentioning that using a watch with BT technology is one thing, but if you're planning on using it as a standalone device you may want to look into whether or not you'll be able to modify the settings to the BYOD T-Mobile data & APN settings.
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