Google unveiled the latest version of its Android platform, 4.1 (Jelly Bean), at its I/O developer event this week.

The company said that it will offer a “smoother and more responsive UI across the system, a home screen that automatically adapts to fit your content, a powerful predictive keyboard, richer and more interactive notifications, larger payload sizes for Android Beam sharing and much more.”

And in a blog post, it also noted that “Jelly Bean wouldn’t be complete without a healthy serving of new APIs for app developers.”

Among the new features available for Android 4.1 developers are: expandable notifications, enabling apps to display “larger, richer” messages and with users able to initiate actions from the alerts; an updated Android Beam content sharing service with Bluetooth data transfer support (NFC is still used to initiate the transaction); new APIs for accessibility services, to enable developers to handle gestures and manage accessibility focus; low-level access to platform hardware and software codecs; and network bandwidth management, to detect metered networks including tethering to mobile hotspots.

Also on the feature list are resizable app widgets; support for higher resolution contact images; APIs to enable apps to discern the input types available including peripherals; and an updated Android Browser with improved HTML5 capabilites.

Other Android highlights announced include smart app updating for Android 2.3 devices and onward, where only parts of an app that are changed are downloaded to a user’s device, cutting file sizes to around one-third; app encryption, with downloads tied to a hardware-specific key to reduce piracy; and updated support for Google Cloud Messaging in devices running Android 2.2 or later.

Google noted that it is currently offering a preview Android 4.1, and is still finalising the API implementations. It will be releasing a final platform in “a few weeks” for developers to use to build and publish commercial Jelly Bean apps.

Google also said it intends releasing the platform to open-source, but has not disclosed timeframes for this.