Ticketfly Inc., a San Francisco-based technology company among several posing a challenge to Ticketmaster, is acquiring WillCall Inc., a crosstown rival that turns your smartphone into a mobile wallet at live events.

The move is meant to expand WillCall's data-collection and payment service to more ticket buyers. Ticketfly has grossed some $400 million in ticket sales and sold 16 million tickets so far this year.

For comparison, Ticketmaster parent Live Nation Entertainment Inc. made $2.56 billion in concert and other ticketing revenue in the first half of the year.

WillCall CEO Donnie Dinch and Ticketfly CEO Andrew Dreskin say the deal is meant to make buying things at concerts easier while providing promoters with data to help them market to high-spending fans. Terms were not disclosed.