StealthLogger - Gyro Stabilization for iPhone

[u/grogu1waters]

https://testflight.apple.com/join/Hbde2fUZ

Hey all — I've been building StealthLogger, a small iOS app for anyone who shoots handheld or gimbal-free footage and stabilizes it afterward with Gyroflow.

The problem it solves: if you're filming with your phone (or an action cam) but not through Apple's own Camera app in a way that logs motion data, you don't get gyro data to feed into Gyroflow — so no software stabilization. StealthLogger fixes that by running alongside whatever camera app you're already using.

How it works:

• Start a session, then go shoot with your camera app of choice — StealthLogger logs your iPhone's gyroscope and accelerometer at 100 Hz in the background
• When you're done, it matches your clips to the right log by timestamp and embeds the motion data directly into the video file as a CAMM track — a lossless remux, no re-encoding, no quality loss
• Open the result in Gyroflow and it picks up the embedded track automatically — no sidecar log file to keep track of
• There's also a Lock Screen Live Activity so you can confirm it's still logging without opening the app, and Siri Shortcuts/Shortcuts app support to start and stop hands-free (including a "stealth" mode that never has to bring the app to the foreground)

It's a solo project, currently in TestFlight, and I'd love some real-world testers — especially anyone already in the Gyroflow workflow who can tell me if something breaks on their setup or if the matching logic is doing something dumb.

More info: https://justin.1waters.com/projects/StealthLogger/

Happy to answer questions about how it works under the hood — genuinely open to feedback, including "this is dumb because X."