Phone? Check. Internet? Check. Twitter? Check.

That’s all commuters need to tweet their way to a free Coca-Cola t-shirt and can of Coke when they spot the Tweet Shop at one of several major London train stations this month.

When consumers spot the Coca-Cola Tweet Shop, they’re prompted to send a happy tweet using the hashtag #choosehappiness before watching the magic unfold. The branded t-shirts, emblazoned with the iconic Coca-Cola logo, come in four colours depicting the four Coke variants, so tweet shoppers can choose their favourite tee!

It’s one of the many ways Coca-Cola is raising the roof on London’s happiness levels, and measuring the mood of the capital with the Coca-Cola Happiness Meter.

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