Update: The company later clarified that there was a clerical error and that the total amount raised is $12.5 million, not $12.9 million as we originally reported. 

Flexibility has never been wireless services’ strong suit — they’re sold in bulk plans which are often too big or too small for one’s ideal usage.

But Andreesen Horowitz-darling ItsOn has been working to alleviate this (and the potential overloading of our infrastructures), and it’s now $12.5 million richer.

Today the company filed a Form D with the U.S. Securities and Exchanges Commission for a new round of funding. According to the document, it is seeking to raise a total of $20 million, and two investors have signed on so far.

ItsOn was founded in 2008, but it came out of stealth in October 2012, when it also announced $15.5 million in new financing from Andreesen Horowitz, SV Angel, and an investor group led by Jim Davidson, as we previously reported.

The company is looking to provide solutions for the major problem it’s foreseeing: Our wireless data networks are too old and unprepared to handle the massive demands we are rapidly putting on them.

To do so, it released its first product in May 2013, Zact, which helps smartphone users control in real-time their data plans and usage. They can “customize a plan of any size and configuration based on usage, share that plan with other people and devices at no additional cost, and even set parental control features such as curfews, allowed apps and contacts,” according to the company’s website.

Another aspect of ItsOn’s potential offerings is sponsorship. Brands could eventually pay for discrete kinds of data, such a offering free data if its used for their app, to stream a proprietary video on YouTube, and so on.

The company was founded by Gregory Raleigh and Charles Giancarlo and is based in Redwood City, Calif. It previously raised a total of $27.9 million.