Kovion CCTV

Most of us have an old phone in a drawer. Kovion CCTV turns it into a security camera you can watch from anywhere. Open the site, point the phone at what you want to keep an eye on, and watch it live from another phone or a laptop.

There's nothing to install and no account to make. It runs in the browser and can be added to the home screen like an app.

What it does

• Live HD video. 720p at up to 60 frames a second by default, sharper 1080p if you want it, or a data saver mode for weak signal.
• Two-way talk. Hold to talk through the camera phone, or just listen in.
• Motion alerts. You get a snapshot the moment something moves.
• Anti-touch alarm. If someone picks the camera phone up, it sounds a siren and tells them to put it back.
• Sirens, alarm tones and voice warnings, set off remotely from the viewer.
• Invites with permissions. Share a code that lets someone just watch, or also talk and trigger sounds. Revoke it and everyone who used it is disconnected.

How we built it

The video travels between the two devices over WebRTC, directly whenever the network allows it, and it's never recorded on our servers.

The hard part was keeping a stream alive on real-world Wi-Fi. The viewer checks every second that frames are arriving. If the picture freezes it asks for a fresh frame, then reconnects, then rebuilds the connection, until it's moving again. The camera side restarts a stalled encoder by itself. Motion detection runs in a background worker on tiny downscaled frames, so it doesn't drain the battery.

Try it

It's live and free at cctv.kovion.site. You'll need two devices: one to be the camera and one to watch.