Plenty of studies have shown that iPhone users upgrade their handsets more often than other smartphone users. But what should you do with that old iPhone once you have upgraded to a new one? There are plenty of good options out there, and some of the most common ones include selling your old phone using a site like eBay or Craigslist, trading it in for credit toward the purchase of a new phone, or giving it away to a friend or loved one.

But there’s another option you might not be aware of that is incredibly useful and completely free.

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“Smart Home” is a term you’ll see more and more in the coming years as Internet-connected devices become more affordable, but you’ll still need to make a somewhat significant investment to turn your home into a Smart Home.

If you’re just looking for one or two specific solutions, however, there are plenty of nice affordable choice out there.

For example, a nifty free app called Manything will let you instantly turn any old iPhone, iPad or iPod touch into a motion-sensing security camera without paying a penny. The app gets installed on your iOS device, and then you can place it anywhere you want.

Manything will stream video that can be viewed anytime you want through the app on your phone. It also automatically begins recording anytime it senses motion, and it can send an alert to your phone as well.

A video detailing the app follows below, along with a link to download it for free.

Download Manything