When Apple introduced the first iPhone in 2007, many AT&T customers rushed to sign up for the now-defunct unlimited data plan, viewing it as the best way to cover all of their data needs all the time. But ItsOn thinks the answer is actually flexible personalization.

Today, the San Mateo, Calif.-based company is officially announcing $12.5 million in new funding to help fuel its expansion plans. Tenaya Capital led the round, with participation from current investor Andreesen Horowitz.

Back in late Oct. 2012 when ItsOn came out of stealth along with a funding round, it made the bold claim that it would redefine how wireless data plans are packaged and put control back in consumers’ hands. It has been building technology that will allow for more granular and real-time segmentation of wireless data by both networks and customers.

Since then, it has released its first product, Zact, in partnership with Sprint, essentially as a test of how this would all work out.