Thumb Junkie
The user of many a thumb. Also known as a Thumb Jockey, this is used to describe someone who is not such a fan of the traditional "2 in the pink - one in the stink" method.
Haw mate she's a pure thumb junkie
thumb junky
A Facebook user desperate for the little hit of a 'like' on his post.
Dave is constantly flooding pics of his crappy car on the Facebook group page. He needs the Likes. He's such a Thumb Junky.