If you’re launching a startup today, your best bet is to build on top of a widely adopted platform — Facebook, anyone? — rather than try to rally users to a completely new site.

That’s the smart course LeaAnna Hernandez took with MyMic, a still largely undiscovered app (2,797 Likes) that lets anyone on Facebook record a message that you can post to your own wall or share with a friend. (The first 20 seconds are free.)

MyMic won the best startup award at Latino 2, a gathering of 160 thought leaders, chiefly from the Latino community, on June 11 in Mountain View, Calif.

I caught up with Leanna, creator of MyMic, toward the end of the conference.

Watch, embed or download the 5-minute video on Vimeo

“I would love to be the audio version of YouTube,” LeaAnna says.

Coming next: a mobile MyMic app and a MyMic website, where users will be able to record audio files and share them with anyone, whether or not they’re on Facebook.