Frequently Asked Questions

Viper Tuner is a professional piano tuning application that uses physics-based acoustic modeling and high-resolution DSP. Unlike traditional ETDs that interpolate between sparse measurements, Viper Tuner provides comprehensive harmonic analysis and multiple tuning approaches.

Viper Tuner is designed for professional piano technicians. While students and hobbyists are welcome, the interface and features assume familiarity with piano tuning concepts like inharmonicity, temperament, and octave stretch.

Viper Tuner is free during the beta period (through end of March 2026 for existing testers). Pricing for the official release hasn't been announced yet. Beta testers will receive discount pricing as a thank you for their feedback.

Viper Tuner offers two primary tuning workflows plus a suite of aural tools:

• Classic: Uses universal treble physics combined with real bass measurements. Fastest path to a high-quality tuning—the daily driver for most work.
• Measure: Full 61-note scan with high-resolution DSP, generating millions of data points for concert-level precision.

Aural tuning tools (temperament sequences, interval checks) are available from the Tools menu—accessible during any session, not a separate mode.

A Progressive Web App (PWA) is a website that can be installed on your device and used like a native app. Once installed, it gets its own icon, runs full-screen without browser bars, and works offline.

Think of it as an app that doesn't need an app store. See our Get Started page for installation instructions.

We're using a PWA for the beta because it allows rapid iteration based on feedback. App store review processes can take weeks, and we want to ship improvements quickly.

Native iOS and Android apps are coming in the first half of 2026 and will eliminate PWA limitations like microphone permission issues on iOS.

Installing as a PWA gives the app its own storage space. If you sign in before installing, you'll need to enter your code again after installation because the browser and the installed PWA have separate storage.

Install first, then enter your code once in the installed app.

This is a WebKit (Safari) limitation, not a Viper Tuner bug. Apple's PWA implementation doesn't persist microphone permissions the way native apps do.

The native iOS app (coming first half of 2026) will have persistent permissions. We know it's annoying—we deal with it too.

On iOS, the microphone can sometimes freeze after the device sleeps or switches apps. Try these steps:

• Tap the "iOS Mic Frozen?" button on the home screen
• Close and reopen the app
• If that doesn't work, go to Settings > Safari > Clear History and Website Data, then reinstall

The native iOS app won't have this issue.

Screen wake lock behavior varies by browser and OS. iOS Safari doesn't reliably support the Wake Lock API in PWAs.

Workaround: Increase your auto-lock timeout in Settings > Display & Brightness > Auto-Lock. The native app will handle this properly.

Viper Tuner requires WebGL, WebAudio, and WebAssembly with SharedArrayBuffer support. Tested and working:

• iPhone 15/16 (iOS 17+, installed as PWA via Safari)
• Chrome on Android
• Chrome, Firefox, Edge on Windows/Mac/Linux

Run our compatibility checker if you're unsure.

Common issues:

• Outdated browser: Update to the latest version
• Security extensions: Ad blockers or privacy tools can block required features. Try a clean browser profile.
• Corporate network: Some networks block WebAssembly. Try a personal network.
• In-app browser: Links opened from Facebook, email apps, etc. use limited browsers. Open in Safari/Chrome directly.
• Private/Incognito mode: Some features are disabled. Use a normal window.

Your access code is deterministically generated from your email address. Simply register again with the same email and you'll get the same code.

Yes. Install the PWA on each device and sign in with your email and access code. There's no device limit during the beta.

The beta preview runs through the end of March 2026 for existing testers. Beta testers will receive discount pricing for the official release. Keep your access code as proof of participation.