Compatible with GSM carriers such as AT&T and T-Mobile, but not compatible with CDMA carriers such as Verizon and Sprint. 4G LTE / 3G / 2G network supported (please check with your phone carrier for compatibility and data plan details).
GSM SIM Card support
: If you need a data connection while you're out and about, you can purchase a data plan from a GSM service provided (in the United States, this would include AT&T and T-Mobile) and then use their SIM card in this tablet. That way, you don't need to track down a WiFi hotspot to check your email or browse the web. I've used the free service available through the FreedomPop Global SIM
and it works fine, just make sure to set your data limit accordingly in "Settings".
SIM card slot is for navigation off line.
With GPS, your phablet can be turned into a handy travel assistant as a GPS navigator with SIM card inserted (Please install appropriate navigation app, data will be consumed).
Info from here
Have a look at the videos.
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