Starbucks to serve coffee with a side of free wireless charging

Sometimes you're not the only one needing an energy boost at a coffee shop. Starbucks has teamed up with Duracell Powermat so ailing smartphones can wirelessly charge alongside their owners at the popular caffeine outlets.

The programme is so far only available in the US, but means that customers will be able to place their compatible devices on so-called Powermat Spots dotted on Starbucks counter tops and tables.

The service already rolled out in shops across California, and Starbucks has promised pilot programs in Europe and Asia within a year.

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Coffee chains like Starbucks have been preoccupied in recent years trying to find new ways to encourage customers to stay longer (and buy more caffeinated beverages in the process.) Free Wi-Fi and mobile payments have consequently become popular as a way of ensnaring the growing number of mobile workers who stop by for a quick cuppa.

Operating across more than 20,500 stores round the world, Starbucks has led this trend of experimentation. In 2010 it started offering customers free Internet and this year has begun testing a service that allows customers to order ahead of time on their smartphones.

Still, that hasn't stopped its shares dropping by 4.6 per cent so far this year. Perhaps this latest venture can boost interest again.