Snappy

Inspiration

I have ADHD, and am a naturally fidgety person. I recently learned the macbook's chassis can be used as an input source, and while building an app to make use of that, I had a random thought of "what if instead of tapping your chassis, your macbook could "hear" your fingers snap out loud?".

So began my journey to see if my 3am idea could actually work, and I'm super pleased with the results!

What it does

You snap your fingers once or twice, your macbook's microphone captures it, compares it to your past fingersnap's recording (like an audio fingerprint), and then approves it as input to launch an action of your choosing. You can do things like open up a website, open an app, open up a workspace/set of apps, and even delete all your open tabs hilariously as if Thanos snapped his fingers near your macbook.

How we built it

I looked online for a GitHub repo to see if this was even possible, and I found somebody did it with Windows OS by clapping https://github.com/Yutarop/two_claps_open.

Once I saw this as possible, I gave the link to Codex and straight up asked it to make snapping a reality.

I did a bunch of testing with codex to make it recognize my snap and shared a lot of early demos online and with friends to see things that I could add to make this app even better.

Challenges we ran into

There were a ton of false positives. I'm not a machine learning expert by any means, so I would drill codex and ask if there was anything that we could use. I also tried to pull examples from the original clapper, where you clap your hands twice and the lights turn on and off, from back in the day to see how that worked and if we could use first principles thinking to fix our errors.

Also, the UX was all over the place, so I worked back and forth with Codex to streamline the menu bar app to make it very easy for first-time people using it.

Lastly, I originally focused on the gesture of double snapping my fingers twice for the gesture to be complete and to kick off in action. I got a comment from a potential user who said that he has difficulty snapping his fingers twice in a row. He asked for a single snap. I spent quite a lot of hours on that feature, and Codex was able to fix it, so I was very happy about that! https://x.com/emanperez28/status/2078971737111228861?s=20

Accomplishments that we're proud of

Getting the app to work lol. It's crazy to me in 2026 that your MacBook can recognize your snap and double snap. I also love how we got to train it, and I think accuracy is somewhere in the 85 to 90% range.

What we learned

I learned to build out the core feature set first, before moving on to design the UI and UX of that. For me, the functionality came first before building out anything else. Also learned that I don't need to have a data set of previous fingersnaps stored which was clutch! I also didn't know that you could build something like this using Swift. I thought only Python could do something like this.

Apple ML also helped reject:

• keyboard typing
• clicking on the trackpad
• noise from my macbook's speakers that could resemble snapping
• other outside noise that could interfere with the training

What's next for Snappy

I'm going to launch this as a product and sell it for a one-time fee for a lifetime license for consumers. This is a lot of fun, and I'm just gonna keep on making content for it to promote the fun features. I didn't expect so much love from my community on this, and I really can't wait to put it into the hands of everyday users.

Built With

• swift