Google revealed that it paid out $5 billion in revenue to developers over the past year, as it previewed the next version of Android and showcased a raft of new features and tools.

“We’re seeing tremendous momentum and we’re very excited as this directly translates to developers building their livelihoods on our platform,” said Sundar Pichai, SVP for Android, Chrome & Apps, adding that developer payouts were two and a half times higher than the previous year.

The Android ‘L’ developer preview includes more than 5,000 new APIs which enable technology to be developed for a range of form factors.

These include Google Fit, a single set of APIs to manage health and fitness data on apps and devices with which app developers can integrate their products. This is similar to Apple’s HealthKit SDK which will be part of the forthcoming iOS 8.

“Fit takes away the complexity of handling multiple sources, giving a unified view of a user’s fitness activity,” said Ellie Powers, product manager Google Play. Partners already making use of Google Fit include Nike, Adidas and RunKeeper.

Another new API enables search suggestions based on content that users recently accessed, rather than just using previous search terms.

Android L features improved notifications which provide direct access to apps from the lock screen, as well as head-up notifications when users are performing another task. It also has a new keyboard UI, quick settings and ‘do not disturb’ mode.

Other features include the ability for smartphones to be unlocked using Bluetooth connectivity on Android Wear smart watches.

Google Play Games, which added 100 million users in the past six month, gained new functionality, including a profile that enables players to access saved games and ‘quests’ to gain rewards.

In addition, direct carrier billing was introduced for tablet devices, allowing users to charge their Google Play purchases to their phone bill.

Android L gains new graphical capabilities called ‘material design’, which gives the UI a three-dimensional look and feel, including shadow and animated transitions between apps and menus.

There is also new support for colour schemes, grids for consistent designs, and a unified set of style guidelines.

Google has also looked at performance, designing Android L to run on the ART runtime which was previously a developer option in the previous KitKat version of the OS. ART offers much improved performance compared to Dalvik, the engine that previously ran Android apps.

The acquisition of mobile cloud testing company Appurify was also announced. The company’s technology helps developers monitor how apps behave, device performance, power consumption and stability. Appurify offers a freemium service across Android and iOS.