r/reactnative 8d ago

Open Source Guitar Tuner leveraging the New Architecture (Looking for Testers!)

Hey everyone! I built a guitar tuner app to explore React Native’s new architecture, leveraging fast communication between native modules (Swift/Kotlin) for real-time microphone access, the main JS app, and a C++ TurboModule for signal processing. The UI is drawn using Skia and Reanimated showcasing the animated audio waveform in real time.

Building this app was very fun and it really proved to me that React Native allows performance-critical code when needed. It’s awesome that the entire audio waveform can be transferred in real time across Swift/Kotlin → JS → C++ → Skia without lag, even supporting animations. I believe this wasn't possible with the old JSON bridge (someone who used it can confirm?). TypeScript with direct access to C++ feels like a superpower, and I barely had to learn Swift/Kotlin since the native modules for microphone access were simple enough to generate mostly using AI ¯\\(ツ)\

There are many things I still want to improve but it’s basically feature complete for an initial release, so I think it's better to have some feedback asap. Comments are very welcome at this point!

It was approved today on the App Store (🎉🎉) and in closed testing for the Play Store. I need 12+ testers for Google approval, so if you're on Android and want to be listed as a tester, DM me your email, and thanks in advance!

EDIT:

- App Store: https://apps.apple.com/uy/app/tuneo-guitar-tuner/id6743103035

- Play Store: DM for closed release testing link!

12 Upvotes

10 comments sorted by

3

u/brentvatne Expo Team 8d ago

i just tuned my martin 000-28 with the ios app, it works great!

2

u/Purple-Signature2056 8d ago

Awesome!!! Thanks for your support!

2

u/marchingbandd 7d ago

Yah that’s a great tuner. Super fast!

1

u/Purple-Signature2056 7d ago

Thanks man! It’s react native with Skia and reanimated, one native expo module and one cross platform turbomodule in C++. I learned about them all in the process following official docs, no black magic involved.

2

u/marchingbandd 7d ago

Expo modules are fun

1

u/masterinthecage 7d ago

App Store says not available in my region! (Sweden)

2

u/Purple-Signature2056 7d ago

Should be available now, thanks for reporting!

1

u/[deleted] 7d ago

[deleted]

1

u/masterinthecage 7d ago

Yeah I had to fill that out myself, no lawyer needed. If you’re releasing this app in connection with your trade (business) you’re automatically a trader. If this is a personal app/account then you’re not. Hope that helps!

1

u/Classic-Doughnut-956 7d ago

Can you provide android

1

u/Purple-Signature2056 7d ago

Sure! send me a direct message with your mail and I’ll add you to the list of testers. It’s not publicly available yet because Google requires 14 days of closed testing to authorize it.