Got a banged-up old smartphone lying around in the bottom of a dusty drawer at home? Little did you know that it's just one app away from becoming your new smart home security camera...

There’s a whole army of newfangled smart cameras ready to cast a beady eye over our homes – Netatmo Welcome, Piper NV and Ulo to name but a few of them. But they can be expensive, forcing us to question the price we’re willing to pay for safety. If you’re looking for a cheaper way to get set up with a home surveillance system, one of these clever apps for your spare old smartphone could be the perfection solution.

ManyThing

ManyThingManyThing is an IFTTT-compatible app that turns practically any old iOS or Android phone into a cloud-connected smart security camera. Simply download the ManyThing app onto your old handset and your current device, pop your old phone at your preferred vantage point, and enjoy instant access to a live-stream of footage from inside your home wherever you are.

Just like any all-singing, all-dancing smart security you can buy these days, ManyThing gives your phone motion-sensing powers, which triggers an alert on your current device every time your old handset picks up on unusual activity. If you’ve got pets pottering round the house, you can even use the app to set masked zones to prevent your new makeshift security camera from reacting to their tail-wagging and sofa-jumping.

Because ManyThing saves your footage to the cloud, you don’t have to worry about your old phone’s puny memory space getting filled up too quickly. It also means you can access all of your recording via your device or the ManyThing desktop site, where you can also create clips, make time-lapse videos, and save and share your favourite moments.

With IFTTT compatibility, you can also create smart home recipe involving your new security camera, like having it switch on automatically when you leave the house.

The ManyThing app is free, but prices for various subscription packages cost up to about £17.99 per month, with the option to use ManyThing with up to 5 old smartphones in your home.

ManyThing is available to download for both iOS and Android devices.

AlfredAlfred app

Like ManyThing, Alfred takes advantage of your old phone’s ability to detect motion, transforming your chunky old monster of a keypad into a smart-streaming smart home eye. To use Alfred, all you need is two phones and one Gmail account, which acts as the virtual link between your two devices.

Again, you’ll get a push notification to your current phone every time your old phone picks up motion from wherever it’s perched at home, and you can also watch a live-feed of all the action you’re missing out on when you’re not in.

While Alfred doesn’t link up to IFTTT for some clever home automation hocus-pocus like ManyThing, it does have a handy two-way talk feature, which lets you chat with people (or animals) in your house when you’re not in. Presumably, this is more for the purposes of cajoling your dog off the sofa than it is for talking to people at home, because obviously, you’ve already got a phone for that. With Alfred, you can also use your current phone as a remote control for activating your old phone’s camera switch and flash.

Alfred is available to download for both iOS and Android devices.