Concert Kiss

The Hero and the Love Interest have just saved the day, and they've done so in a very large, very public place with a very noticeable audience - say, a theatre performance, or an orchestra recital. Having saved the day, our heroes are receiving a round of applause (although the audience may not know exactly why, seeing as from their perspective all that's happened is that a couple of jokers have just burst in and completely stage-crashed what might have been a very interesting performance; usually it's because someone very prominent, such as the President of the United States or the Pope, is present and has started applauding because he thinks what's happened is part of the performance or is a lot more entertaining than the scheduled show).

Then, swept up in the moment, the Hero and the Love Interest decide that, then and there, they'll confirm their recently developed feelings for each other. By kissing in front of everyone. It's a major 'awww' moment, and usually to make it even more romantic, the applause increases in volume and intensity; ah, True Love, now this is worth applauding!

A subtrope of The Big Damn Kiss. See also Smooch of Victory.

Examples of Concert Kiss include:

Anime & Manga

Averted in Blood+: The hero defeats the Big Bad on stage at an opera house, her Bodyguard Crush confesses his love to her, and they kiss... in front of an audience of two. Also, the whole scene was rather dark, instead of straight-up happy like most that follow this trope.
Speed Racer and his longtime girlfriend Trixie have a discussion early in The Movie about his lack of romance. The best idea he can come up with is kissing her on the lips after winning the big race. At the end of the film, in front of tens of thousands of screaming fans and an international TV audience, he does just this. The camera flashes become heart shaped as this happens.
Julia and Ran share their First Kiss at the beginning of a ZLAY concert in Strawberry Shake Sweet. Of course, the whole thing was set up by the oh-so-Genre Savvy ZLAY band members in the first place.

Films -- Animation

Louie and Cecilia in We're Back! A Dinosaur's Story. Near the end of the movie, after calming the dinosaurs with The Power of Love, they both kiss in a crowd of people in a circus show.

Films -- Live Action

The end of the Goldie Hawn/Chevy Chase movie Foul Play.
Averted in Music and Lyrics; although the romantic climax does occur at a concert, the climactic pash between the two lovers occurs in the wings, out of sight whilst the concert continues apace.
Ghostbusters: After the Ghostbusters defeat Gozer, they come out in front of the building to the cheers of the crowd, and Peter Venkman kisses Dana Barrett.
Under Siege: Casey Ryback kisses Jordan Tate after the bad guys are defeated.
Judge Dredd: After Rico is defeated, in a rare Gender Flip, Judge Hershey kisses Judge Dredd.
Galaxy Quest has the climactic kiss on stage at a convention for the eponymous TV show. A fan is seen fainting, apparently due to her Shipping being "confirmed".
Anger Management: At Yankee Stadium. In fact, it in and of itself was the climax of the story, given that the main character's anger management counseling was all an elaborate hoax to get him to express his emotions in public.
In Love Actually, the Prime Minister (played by Hugh Grant) finally re-encounters his love interest Natalie in the backstage of a school play, where he professes his love and they kiss... then the curtain goes up.

Prime Minister: Right. So, not quite as secret as we'd hoped.
Natalie: What do we do now?
Prime Minister: Smile. Little bow. And a wave.

Forrest Gump: Forest and Jenny running across the reflecting pool in Washington D.C. and embracing made the crowd explode into applause—mostly since Jenny is part of an anti-war protest and Forrest is in full military uniform.
In Strange Days, Lenny (Ralph Fiennes) and Mace (Angela Bassett) have saved the day, stopped the psycho killer, and solved Iris' murder. Lenny pushes his way through the crowd to Mace, and they kiss just after the clock strikes twelve on New Year's Eve, 2000. Minor subversion, in that no one notices them or pays attention; it's a New Year's Eve party, after all, who's going to pay attention to another couple kissing at midnight?
American Pie 2: This one time, at band camp, Jason Bigg's character totally made out with Alyson Hannigan's character after the final concert performance of the summer.
Literal example at the end of the Josie and The Pussycats movie: After saving the world from musical brainwashing, Josie reunites with sweetheart Alan M, who professes his love to her... while bodysurfing... in the middle of a song... in the middle of a concert being broadcast all over the world. And then they kiss.

Live Action TV

In Glee, Finn and Rachel kiss after performing a duet together at Nationals. The postive crowd reaction is subverted, though- everyone in the crowd thought it was very unprofessional, and it costs them a win.
An episode of The Suite Life of Zack and Cody does this with Cody and Barbara. Accompanied by a kid playing romantic music on his violin.
On The Secret Life of the American Teenager, Ricky and Amy kiss onstage at the former's high school graduation after she accepts his marriage proposal.

Visual Novels

Kira Kira: Pictured above, Kirari kisses Shikanosuke (who was in drag at the time) at the end of their final performance, in front of an audience larger than all of their other performances combined. Bonus points for it being her first kiss.

Western Animation

Linda and Lawrence literally do this at a concert (with a camera projected them onto a big screen as well) in Phineas and Ferb.
Recess: The episode "The Experiment" has T.J. and Spinelli kiss, as an experiment, in front of all their friends and all the kids in the playground, despite T.J. and Spinelli's request in not wanting to kiss in public in the first place, thanks to their friends inability to keep a secret about it.