Pandora just released its first earnings report since going public, and the numbers look like they're heading in the right direction.

Most notably, listeners tuned into more than 1.8 billion hours of Pandora in the three months ended July 31, giving the company a 3.6% share of all radio listening in the U.S.

Both figures more than doubled since last year.

Another good metric: mobile advertising now makes up more than 50% of the company's ad revenue -- that is, about $30 million of the $58 million in total ad revenue. In its IPO filing, Pandora warned that mobile advertising was a big unknown, as the market was still fragmented and immature.

Overall revenue more than doubled from last year to $67 million and generated positive cash flow of $600,000 (compared with a cash spend of $3 million a year ago). Net losses were $1.8 million.