Meet the Graffiti Grip: an app controlled display handle for your tumbler that allows your friends to send messages to it. It is wireless and works with iOS and Android devices. You can use it to show your support for a team, promote your product, or communicate with your friends.
The Graffiti Grip lets you switch off the access sharing mode anytime you want. Yet another interesting Kickstarter project. More info is available here.
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