Facebook's Instagram said on Thursday, September 22 its advertising base more than doubled to exceed 500,000 in the last six months, Reuters reports.

Instagram, the popular picture-sharing app that uses Facebook's ad technology to target highly specific audiences, has gained traction as the preferred platform used by ad agencies for social media campaigns.

The app, which has more than 500 million users, also said more than 1.5 million businesses had switched to its Business Tools program in the two months since its launch earlier this year.

The program allows businesses to promote posts and create custom profiles on Instagram that allows potential users to contact them by phone, e-mail or text messages, Reuters says.

The company, which was bought by Facebook for $1 billion in 2012, is expected to generate $1.5 billion in advertising revenue this year, according to research firm eMarketer.

Instagram said in February that it had more than 200,000 advertisers.