A new patent granted to Google hints at a future Android system with multi-user face unlock security, so a number of users can have their own accounts on a single device.

While design patents often concern precise technical details and are rarely newsworthy, this patent opens up the possibility for manufacturers to create Android devices, that can hold many user accounts.

This means you could have a tablet with user accounts for each member of the family, and each person can log in by being recognised by the front-facing camera.

The 17,000-word patent filing essentially covers methods that allow a "computing device" to recognise one or more users based on facial recognition, and then give them access to apps, documents and accounts specifically assigned to them.

The rest of the patent filing explains how the facial recognition technology works - and it's very similar to how it already works in the Samsung Galaxy S3, so don't expect bulletproof security here.

Android patent

While we found facial unlock on the S3 to be hackable with nothing more than a photo of the user, the patent still proves that Google is investing resources in multiple user accounts for Android devices - and that's more important than specifically how the user logs in.

Although we think multiple user accounts makes more sense on a tablet, the patent filing also mentions using a smartphone: "Implementations can include one or more of the following features. For example, the camera can be physically integrated with the computing device. The computing device can include a phone."

As is the case with design patents, we can't say when Google will implement this feature into its Android operating system - and in fact it may never do so - but it's still interesting to catch a glimpse of what goes on behind the scenes.