Last month Verizon rolled out their new Share Everything plans and in most cases these plans save money for families that want data on several phones or devices. Today, AT&T announced their new Mobile Share plans to compete with Verizon.
Verizon must have gotten the per device price right as AT&T matches the device price for most devices. AT&T actually has a sliding scale for adding each smartphone so the per device cost for multiple smartphones decreases as you increase your data allotment. You can see the AT&T options in the image below:
If you compare to Verizon's Share Everything plans, these plans are priced very much the same unless you add more devices and more data per month. AT&T has slightly higher data fees for 4GB or more, but then the per device smartphone fee decreases so heavy data smartphone users can see a savings. Mobile hotspot service is included with both carriers on compatabile smartphones. Verizon charges $10 per additional GB and AT&T charges you $15 so make sure you sign up for the allotment you need. You should then look at which carrier works best for you since the costs are essentially the same. Verizon does currently have much greater LTE coverage though.
I am still a T-Mobile customer with no shared data option so have just two phones with data and the rest with voice and text. T-Mobile hasn't yet decided to join the shared data trend. As my daughters get older they may want data, so I am considering a move to Verizon (AT&T didn't work out so well for us last time and no one is willing to try them again.)