Questions and answers

Thin Walls is an iPhone app that keeps a night-by-night log of estimated noise levels. You start a log before bed. In the morning you see when it got loud, for how long and how often, as estimates from your iPhone microphone. It is a personal log, not a certified sound level meter.

People who live with noise in US apartments, condos and houses keep asking for a simple log: when it got loud, for how long and how often, without recording their home or sending data away. Thin Walls was built to answer that. See what people asked for.

Tap Start before you go to sleep. The app estimates the sound level every second and keeps going while the screen is locked. In the morning, open the app and tap Stop, then Save. See Help: Log a night.

Place the iPhone a few feet from the wall, ceiling or window the noise comes through. Not at your bedside. Put it only where you are allowed to leave a device. See Help: Where to put the iPhone.

No. A sound level meter is only for the optional calibration. Without calibration the app shows dB above quiet, a difference from that night's quiet level. After calibration it also shows dBA. See Help: dB above quiet and dBA.

Thin Walls is made for iPhone and needs iOS 17.0 or later.

Logging does not need a connection, and the app does not send your levels, times, notes or reports anywhere. Buying or restoring the unlock goes through the App Store, which needs a connection.

Yes. Tap Start before bed and the app keeps going while the screen is locked. Keep the iPhone charging and do not put it under a pillow or blanket.

If logging stops, for example after a call, you get an alert. Allow notifications to see it. The app also tries to start measuring again, but do not count on it. Time that was not recorded is shown as not recorded, and the app never fills it in. See Help: If logging stops.

Turn on microphone access for Thin Walls in your iPhone Settings, then start the log again.

It is how far above that night's quiet level the sound got. The quiet level is how quiet the room was in the first 10 minutes. It is a difference, not a sound level, so it is not comparable between nights.

The threshold is your quiet level in the first 10 minutes plus 10 dB. An event is a louder period that the app finds by comparing its own estimates with that threshold. If the first 10 minutes were noisy, the quiet level can come out too high, and the app marks those nights. See Help: Threshold.

Tap the event, choose My own sound, then Save. The event stays in your log, but it is not counted in the totals on screen or in reports. The report lists how many events you marked, when each one started and how long it lasted. See Help: My own sound.

Yes. You can add a note to any event: footsteps, music, bass or party, voices, dog barking, door or banging, traffic or street, construction, machine or hum, my own sound, or other. The app does not decide what made a sound. The labels are yours.

On the Nights tab, tap Make report. Choose the type (Detailed log, Landlord / HOA or Night Summary), choose the dates, then create a PDF or a ZIP. Your first full report is free. See Help: Make a report.

Yes, in the optional Recipient field, for example a property manager, an HOA board or a city office. It is printed after "To:" at the top of the PDF. Leave it empty to write it by hand. It stays on this iPhone.

We cannot promise that. None of them has promised to accept it, and rules differ by place and by person. If your situation is serious, consider asking a lawyer or a local tenants' organization. This page is not legal advice.

After you create a PDF or ZIP, the app shows a SHA-256 file fingerprint. If a file you compare shows the same value, it is byte-for-byte the same as the file you exported. It does not show who made the file, that the sounds happened as described, or that nothing was changed before export.

Tap Share PDF or Share ZIP. The iOS share sheet opens, and you pick one of the options your iPhone offers. You can also share the chart of one night as an image.

No. Audio is analyzed on your iPhone as it comes in. It is not recorded, saved or sent anywhere. The app saves sound levels, times and your notes in the app on your iPhone.

The app does not save audio. The microphone can still pick up sounds in the room while it logs, and the app turns them into level numbers. Whether using it is lawful where you are depends on the laws that apply to you. You are responsible for following them.

On your iPhone. We never receive your levels, times, notes or reports. Your records may be included in your own iPhone backups. Read the Privacy Policy.

In Settings, tap Delete all nights. It removes every saved night from this iPhone. Nights can only be deleted all at once, because each night's fingerprint depends on the one before it. Files you already exported are not affected.

Overnight logging, nightly summaries and charts, notes, chart images and data export are always free. Your first full PDF and ZIP report is free. Unlimited PDFs and ZIPs are a one-time purchase, not a subscription. The price is $9.99 in the US. The App Store shows the final price in your currency before you buy.

Tap Restore Purchases. It is on the purchase screen and in Settings. Use the same Apple Account you bought with.

Yes. Thin Walls is for adults 18 and older. To accept the Terms of Use you must be at least 18 years old and have reached the age of majority where you live.

The Help page follows the Help screen in the app, section by section. The Terms of Use and the Privacy Policy have the exact wording.

Write to contact form. Please do not include names, addresses or unit numbers of other people.