Having been the bookies' favourite for most of the series, the gymnast troupe beat comic dance duo Twist & Pulse.
Speaking after hosts Ant & Dec announced the result, the group said: "This is unbelievable, it shows our hard work has paid off."
Twist & Pulse said upon finishing as runners-up: "I can't believe it at all. Thank you for everyone, and out of all those people who audition, it's amazing [to get this far]."
Drummer Kieran Gaffney finished in third place. Acts outside the top three included Tina & Chandi, Paul Burling and teen boyband Connected.