Tesco is trialling an app for smartphones running Google Android that helps users navigate their way round the store.

The app, which currently only works at a Tesco Extra branch, in Romford, Essex, provides users with a map of the store and their location, which Tesco claims is accurate to within three meters. Users can search for the product they want and get direction to which aisle it's located in, as well as being given the shortest route to the specified aisle.

"We won't be rolling this out to customers in general for a while because we have to think about how useful it's going to be. The system involves a lot of infrastructure installation in the stores so we need to get all kinds of people involved in thinking about the customer experience. It would be awful if we did all this work but few customers really used it," said Nick Lansley on the Tech4Tesco blog.

"We must also see how we would put the technology into our production applications and make it really easy for everyone to use. There's also the possibility that the infrastructure is not reliable right now."

The supermarket is appealing for consumers that use to the store to take part in trialling the app. To register your interest, email R&D Project Manager Ben Martin using the address [email protected] and typing "SATNAV APP" in the subject line, to be sent a link to the app, as it's currently available through the Android Market. It's worth noting the app only works on handsets running Android 2.2 or above.