As part of its efforts to ramp its mobile ad business (and thus better monetize its Kindle...

As part of its efforts to ramp its mobile ad business (and thus better monetize its Kindle line), Amazon (NASDAQ:AMZN) has "kicked the tires on a few mobile-ad companies," AdAge reports. One of those companies is said to be JumpTap, one of the largest independent mobile ad networks. It's added Amazon has hired ex-Microsoft mobile marketing chief Jamie Wells to head its ad sales efforts. Millennial Media (MM +3.2%) appears to be getting a lift from AdAge's report.