Google offered a sneak preview of its Glass Development Kit (GDK) and the features that developers will be able to use to build apps for the wearable tech.

Three features have now been opened up for developers: the ability for apps to work offline, real time user response, and deeper access to hardware functionality such as the accelerometer and GPS.

Glass senior developer advocate Timothy Jordan said a full developer preview of the GDK is in the works, with the sneak preview design to allow developers to test, find bugs and tell Google what features are missing.

Jordan demonstrated several apps that use the new GDK functionality, including Word Lens, which translates printed words as you look at them. Other apps demoed included recipe app AllTheCooks and the Strava exercise tracking title.

Until now, developers have been using basic functionality provided by the web-based Mirror API to build Glass apps. The Mirror API allows developers to work with a static version of the Google Glass timeline, respond to user notifications and share information.

Jordan said 83 per cent of Google Glass owners have at least one app developed using the Mirror API on their device.