Mobile marketing and payments company Mobile Embrace has reported a big jump in net profit after doubling revenue over the six months to December.Mobile Embrace uses a payment technology called direct carrier billing, which allows a consumer to buy a digital product or service and have the cost billed to their phone account.Typical products include games, entertainment and sports apps, phone security and analytics products, and information services.The average spend per transaction is A$5 and the maximum transaction allowed by most telcos is between $30 and $40.The company provides payment gateway services for customers of Telstra, Optus, SingTel, the Swiss telco Swisscom and the Norwegian telco Telenor.Revenue growth from this part of the business has been particularly strong, with international revenue rising from around $60,000 a month at the end of 2014 to the current rate of more than $520,000 a month.Unaudited results for the December half released yesterday show revenue up 99 per cent on the previous corresponding period to $28 million and net profit up 73 per cent to $2.6 million.During the half Mobile Embrace acquired the mobile marketing companies Vizmond Media and Marketing Punch, extending its reach into the United Kingdom and France.It also formed a partnership with Telenor's Malaysian subsidiary to provide mobile payment services.