Alarmist LiDAR Motion Detector

Requires LiDAR sensor: iPhone 12 Pro or newer, iPad Pro (2020 or newer). Must be a Pro version.

Turn your iPhone into a motion-activated security camera. Alarmist uses your device's LiDAR sensor to detect movement, capture a photo, and log every event in a detection history that syncs across your devices through iCloud.

• Detect motion and capture evidence automatically
• Review detection history with photos on any device via iCloud
• Run silent: disable the alarm and flashlight for quiet monitoring
• Works in complete darkness using infrared depth sensing

How it works:

1. Place your device on a stable surface, aimed at the area you want to monitor
2. Configure the detection zone and sensitivity (or use defaults)
3. Arm the app
4. Keep the app in the foreground with the screen on

When motion is detected, Alarmist triggers a loud alarm (overrides Silent Mode), turns on the flashlight, and captures a photo. Or switch to silent detection: no alarm, no flash, just a photo and a log entry. Silent detection works best in lighted or dim conditions where the camera can capture a usable image.

LiDAR fires invisible infrared beams and measures depth, not pixels. A person walking through a doorway creates a large, sustained depth change that is unmistakable. This means Alarmist works in complete darkness with no visible light and no camera image required.

Every detection event is logged with a timestamp and photo. Browse your history on the device or enable iCloud sync to see it everywhere. Configurable auto-retention (30, 60, or 90 days) keeps storage in check.

Alarmist is a convenience tool, not a security system. It cannot guarantee detection of all events and should never be your sole means of protection. The device must stay plugged in for extended use, the app must remain in the foreground with the screen on, and locking the screen or switching apps stops monitoring. Technology can fail. Test in your environment and understand its limitations before relying on it. You assume all risk.

I'm a solo developer in Portland, Oregon. I built this app because I wanted it -- something I could set on a nightstand and trust to watch the door while I slept. I named it Alarmist because, well, when you're asleep in an unfamiliar room, overreacting to danger is the whole point.