Midnox — bedroom darkness coach for iPhone
The short version. Midnox runs entirely on your iPhone. Camera images are processed on-device and immediately discarded. We do not upload, store, share, or sell any data. We have no servers, no analytics, no ads, and no accounts. The only thing that persists is a single number — your calibrated dark-room baseline — saved locally on your phone.
Midnox helps you measure how dark your bedroom is by reading exposure information from your iPhone's camera. It produces a traffic-light verdict (DARK, DIM, or BRIGHT) so you can identify and fix light pollution that disrupts sleep.
Midnox requests permission to use your iPhone's camera. When you tap Measure or Calibrate, the app captures a brief image, reads its EXIF metadata (ISO, shutter speed, aperture), computes an approximate lux value, and immediately discards the image. The image is never written to your photo library, never saved to disk, and never transmitted off your device.
One value is saved locally on your iPhone using Apple's standard on-device storage:
Midnox does not collect any of the following:
Midnox includes affiliate links to product recommendations on Amazon. If you tap a product card, your iPhone opens Amazon (in Safari or the Amazon app), and from that point Amazon's own privacy policy applies. Midnox does not see, log, or share which products you view or buy.
Midnox is distributed through Apple's App Store. Apple may collect installation and usage information governed by Apple's own privacy policy. Midnox does not receive any of that data.
Midnox is intended for general audiences and is not directed at children under 13. Because the app collects no personal information from anyone, it does not knowingly collect information from children either.
Because Midnox does not transmit or store data outside your device, there is no server-side database to breach. The single baseline value saved locally is protected by your iPhone's standard sandbox security and is removed when you uninstall the app.
You can remove all data Midnox stores at any time by either tapping Recalibrate within the app (which deletes your baseline) or uninstalling the app. No request to us is required because we don't hold any copy of your data.
If we ever change this policy, the updated version will be posted at this URL with a new "Last updated" date. Material changes will also be reflected in the app's App Store description.
Questions or concerns about this policy can be sent to hello@midnox.app.