How to make phone call over 4G or GSM using Xperia Z LTE (SGP321) tablet with SIM? Messages elsewhere say you can't. If not exactly why not?
With stock Sony ROM you can't do phone calls on the Xperia Z, Z1 and Z2 tablets. Might work if you install an own ROM but I'm not sure.
The new Sony Xperia Z3 Tablet Compact ( http://www.sonymobile.com/global-en/products/tablets/xperia-z3-tablet-compact/ ) can make phone calls, even if you better get a bluetooth headset to make it useable.