noun: The generation born after 1985, which as teens and adolescents communicated by the use of mobile devices such as cell phones. Because wireless mobile devices are small, the thumbs are generally used to type. This led to the use of acronyms to decrease typing time.
adjective: Of or relating to the Thumb Generation.
She uses phrases like TTFN because she's part of the Thumb Generation.
ROTFLMAO is so Thumb Generation.