How to build an Apple Watch door unlocker for $100

If you’ve recently purchased an Apple Watch and want even more functionality out of it, here’s a project to turn your new timepiece into a remote key for your home or office door.

Developed by the clever folks at Make, it uses an app to generate a 128-bit radio frequency (RF) key. Combine that with an RF-enabled Arduino board and you’re on the way to unlocking your door with your watch.

The entire exercise will set you back about $100, which covers the cost of the electronics and a door strike to contain them.

Credit: Make

As well as sharing the video tutorial and detailed instructions on its site, Make has open sourced the code for the project on GitHub. You’ll find everything you need to compile the apps there.

Whether you’re constantly getting locked out of your office or want to secure your study the high-tech way, this is a great use for your Apple Watch.

Make an Apple Watch Door Unlocker [Make via Lifehacker]

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Article image credit: Make

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