The deal follows a competitive pitch that resulted in incumbent Bell Pottinger Business & Brand being unseated from the account.
The independent agency will handle consumer, corporate and social media activity as the brand looks to raise its profile this year.
It aims to encourage more passengers to use smartphones and tablets during flights through a corporate campaign in the aviation, travel and telecoms sectors, as well as a consumer drive.
Several airlines already use the service including Emirates, Virgin Atlantic, Malaysian Airlines and Etihad.
AeroMobile will launch shortly across the Lufthansa fleet.
James Brooke, MD of Rooster, said: 'We live in an increasingly connected world and consumers expect to be able to use their smartphones whenever, wherever. Aero- Mobile is set to make in-flight connectivity the norm.'