T-Mobile's ongoing Uncarrier strategy has already led to roughly 2 million new subscribers the last couple of quarters, while an increasing number of mobile virtual network operators (MVNO) are starting to thrive as cheaper alternatives for those who aren't heavy phone users. AT&T is starting to take notice, it seems, and will at last make plans more affordable for off-contract customers who've paid off their phone or brought their own.

The changes are part of the carrier's new "Mobile Share Value" plans, which will be available starting Sunday. These are essentially the same as existing Mobile Share plans offering a pool of data among a group of subscribers, as well as unlimited talk and text, except that they don't factor in smartphone subsidies for people that aren't actually using them. The savings amount to about $15 per month on service.

Customers on older Share plans who've finished paying their smartphone subsidy and are no longer tied to a contract will see a drop in their service bill by switching to the new plans. Likewise, if you bring your own phone, paid full price upfront or opt for one of AT&T's Next plans, your service is $15 cheaper per month from day one.

The change represents a fairer option for customers who choose to pay for their own handset, which is great news now that there are some great off-contract options such as the Moto G for $180 and Nexus 5 for $350.

The chart below from BGR offers a better look at the expected savings for each Mobile Share Value plan tier.

Source: BGR