The number of mobile app downloads in 2013 will reach 102 billion, with the total value hitting $26bn, according to Gartner.
This compares with 64 billion downloads worth $18bn in 2012. In 2013, free apps will account for 91% of the downloads. Gartner predicts that app store downloads will exceed 268 billion in 2017, with free apps accounting for 94.5% of the total.
"We expect strong growth in downloads through 2014, but growth is forecast to slow down a bit in later years," said Sandy Shen, research director at Gartner.
"The average downloads per device should be high in early years as users get new devices and discover the apps they like. Over time, they accumulate a portfolio of apps they like and stick to, so there will be moderate numbers of downloads in the later years," he added.
Gartner said free apps currently account for 60% of the total available apps in Apple's App Store and 80% in Google Play.
Brian Blau, research director at Gartner, said iOS and Android app stores combined are forecast to account for 90% of global downloads in 2017.
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“These app stores are still increasingly active due to richer ecosystems and large and very active developer communities,” he said.
As a result of the consumerisation of IT trend, the app store concept is also filtering into the corporate sector, where businesses want to make mobile apps available to staff and customers.
Corporate app stores are gaining momentum and are a way to ensure the quality, security and uniformity of their mobile enterprise applications. By 2017, Gartner expects 25% of enterprises to have developed their own app stores and to be negotiating with software suppliers for products that can be added to the ecosystem.
The UK government’s CloudStore, which makes cloud-based apps available to public sector bodies, is an example of organisations making use of the large development community to cut costs and improve services.
French banking giant Credit Agricole has created an app store to provide banking apps to customers and get ideas from customers for new banking apps.
The Credit Agricole Store is a platform that puts developers in touch with the bank's customers. Customers can download any apps they want and make suggestions for new ones. The app store currently has 21 apps and received more than 100,000 visits in its first three months. Apps cover balance checking and fund transfers, as well as one to help visually impaired people use the online banking interface.