Application downloads is expected to reach five billion by 2014, an increase from an estimated 2.3 billion applications downloaded in 2009, according to analyst firm ABI Research.

The firm said that the growing adoption of smartphones which saw sales rise 20% in 2009 and the proliferation of application stores, are the major drivers for this expansive surge.

According to ABI Research, the iPhone’s share of the app market will contract from its 2010 level during the latter part of the forecast period, but it will remain the leading platform for applications.

Bhavya Khanna, wireless research associate at ABI Research, said: “The big beneficiary will be Android, which will see its market share of total application downloads increase from 11% of the market in 2009 to 23% in 2014.This rapid growth is driven by the mass adoption of the Android OS by both vendors and consumers from 2009 onwards.

“There are now more than 14 phones that run the Android OS, and many more will launch in 2010. This, coupled with the rollout of application stores from both smartphone vendors and network operators, will see the iPhone’s share of the total market shrink between 2010 and 2014.”

The firm expects revenue from mobile app sales to decline by 2013, as competition will lead to downward pressure on application prices, and a greater proportion of must-have applications will begin to face competition from free or advertising-supported substitutes.