(Telecompaper) Twitter reported second-quarter revenues of USD 502 million, up 61 percent from the year-earlier figure and above its guidance of USD 470-485 million. Without forex effects, revenues would have increased 68 percent. Advertising revenues rose 63 percent from the year before to USD 452 million, with mobile advertising revenues making up 88 percent of the total. The net loss narrowed to USD 137 million or 21 cents a share from 145 million or 24 cents a share the year earlier. Adjusted EBITDA exceeded the company's target for Q2, coming in at USD 120 million from 54.1 million, representing an adjusted EBITDA margin of 24 percent. Twitter CEO Dick Costolo was pleased with the good progress in monetization but was not satisfied with audience growth. In order to realise its full potential, the CEO said the company had improve in three key areas: it needed to ensure more disciplined execution, simplify its service to deliver value faster, and better communicate that value.