Last updated: September 2, 2026
Decibly is a utility app that turns your iPhone's microphone into an approximate sound level meter. It is not a certified measuring instrument. Use it for everyday reference, not for legal, medical, occupational-safety or regulatory decisions.
By downloading or using Decibly ("the app") you agree to these Terms and to Apple's Licensed Application End User License Agreement. If you do not agree, do not use the app.
We grant you a personal, non-exclusive, non-transferable, revocable license to use the app on Apple devices that you own or control, as permitted by the App Store usage rules. You may not copy, modify, reverse-engineer, distribute or sell the app or any part of it.
Decibly is free to download. Measuring, scenes, the noise alarm, calibration, widgets, the Live Activity and up to three saved sessions are included at no cost. The Evidence Pack is an optional one-time in-app purchase (a non-consumable; there is no subscription and no recurring charge) that unlocks unlimited saved sessions, PDF and CSV reports and summary cards without the Decibly mark. The price is shown in the app and on the App Store before you buy. The purchase is tied to your Apple Account and can be restored on any of your devices with Restore Purchases in Settings or on the purchase screen. If you bought Decibly while it was sold as a paid app, the Evidence Pack is included for you at no extra cost and is recognised automatically. Payments and refunds are handled exclusively by Apple under the App Store terms; we cannot issue refunds ourselves.
The readings shown by Decibly are estimates derived from the microphone built into your device, which was designed for voice, not for acoustic measurement. Accuracy depends on the device model, microphone condition, case, wind, orientation and your calibration setting, and can differ from a professional sound level meter by several decibels or more. The app has not been calibrated or certified against IEC 61672, ANSI S1.4 or any other standard.
The exposure indicator shows general public guidance (NIOSH-style recommended exposure limits) computed from the session's average level. It is informational only, is not a medical device or personal dosimeter, and is not medical, safety or legal advice. If you are concerned about hearing or noise exposure, consult a qualified professional and use certified equipment.
Session data, notes and exported reports are created and stored on your device and remain yours. We never receive them. You are responsible for any reports you choose to share with others.
The app is provided "as is" and "as available", without warranties of any kind, express or implied, including fitness for a particular purpose and accuracy of measurements. We do not guarantee that the app will be error-free or uninterrupted.
To the fullest extent permitted by law, we are not liable for any indirect, incidental, consequential or special damages, or for any decision made or action taken in reliance on the app's readings. Our total liability for any claim relating to the app is limited to the amount you paid for it.
We may update the app or these Terms from time to time; continued use after a change means you accept the updated Terms. We may discontinue the app at any time. You can stop using it at any time by deleting it.
These Terms are governed by the laws of the developer's country of residence, without regard to conflict-of-law rules, except where consumer protection law in your country grants you additional rights.
Questions about these Terms: homasglobal443@gmail.com.