Mobile app downloads are expected to pick up pace this year, due to the rapid adoption of smartphones as well as the proliferation of application stores, according to market research firm ABI Research.

The firm forecasts mobile application downloads to reach just under 6 billion, up from an estimated 2.4 billion in 2009.

In addition, two new smartphone platforms are scheduled to make their debut later this year. Samsung’s Bada OS and Microsoft’s Windows Phone 7 Series, which are expected to be similar to that of Apple’s, will have proprietary application stores.

However, revenues from mobile app sales are expected to decline by 2012, as the increased competition will see downward pressure on application prices; and a greater proportion of must-have applications will begin to have free or advertising-supported substitutes. Many handset makers have also started to bundle applications that allow users to connect to popular social networks, instant messaging and GPS services.

Bhavya Khanna, wireless research associate at ABI Research, said: “The iPhone will continue to be the leading app platform, with a database of over 125,000 applications offering niche and localised content. Other platforms are still playing catch-up, with Android being the fastest gainer among them.

“ABI Research expects that with over 30,000 applications now available, over 800 million Android applications will be downloaded in 2010.”