Meet someone you like and your heart may skip a beat.

Once is applying that toward its dating app, which now syncs with Fitbit and Android Wear to measure your heart rate when you come across a person you find attractive.

There's something to it, as the Once dating app has amassed upward of 600,000 users in only four months, but is only available in the United Kingdom, France and Spain as of now. There's no telling when the app will hit the United States just yet.

With the Fitbit and Android Wear integration, though, Once users can see their heart rate in real time, when they first set their eyes on that day's match. In the updated version of the app, users will even be able to send their heart rate to that match, as reported by Tech Crunch.

Users who don't own wearable tech heart monitors can still use the Once dating app.

The only catch to this is the way Once works — human curators select one potential match per day, not really allowing users to take full advantage of the heart-rate, wearable-tech integration.

Then again, the app's founder and CEO, Jean Meyer, told Tech Crunch that he originally conceived Once during a "slow dating" period in Europe's online dating space.

Meyer adds that the single match per day system ensures what the app aims to be — a significant match — and not a deluge of ones offered up by other dating apps, most of whose potential suitors don't resonate with users. 

"Either the dating platforms are too complex, aimed toward an older demographic or they are focused on casual dating and hook ups," Meyer said.

Would you give Once a try?