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You've finally decided to buy a new Android phone -- maybe the Galaxy S20 or Google Pixel 4 XL -- but now you have to decide what to do with your old one. Sure, you could sell or trade in your previous device (or those other phones you found in a drawer) but it's not the only approach.

If your phone's too old to command a high trade-in value, or you're looking to save some money on a webcam or a Google Home, or maybe you just like to tinker, there are some pretty ingenious ways to repurpose your old device and turn it into something you'll actually want to use.

After all, smartphones are small, powerful computers with storage space and a camera. Your phone makes a handy substitute for lots of other electronics -- you can even turn it into a home security camera or diagnose your car's mechanical problems. Read on!

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Turn your old Android into a webcam

Now is a great time to turn your old phone into a webcam. You can use a number of free apps -- including Zoom or Skype -- to improve the quality of your video chats during quarantine. Getting started is easy, and we give you all the tips you need for a top-notch setup. Remember, even an older phone's main camera could still be better than your laptop's built-in webcam -- or no webcam at all.

Hyperkin

Convert your old Android into a Nintendo Game Boy

You can play video games everywhere you go when you turn your Android into a Nintendo Game Boy. All you need to get started is a compatible Android phone and a Hyperkin Smartboy Mobile Device.

In order to play the games, you'll need to purchase Game Boy cartridges (unless you still have them). But you can also play Game Boy Advance ( ) apps if you don't have the retro cartridges.

Store your photos on the old phone

Images take up so much storage space on your phone, so store them on your old phone. You can use your new device to take the photos and then send them to your older phone to free up space.

You can also use your old phone as a camera and take it places you normally wouldn't want to take your new phone. For example, if you go to the lake or beach, you can take photos without worrying as much about dropping your phone in the water.

Use your Android as a universal remote

It's great having one remote that can do everything -- think Click, the Adam Sandler movie. OK, maybe not that extreme. But being able to control all of your devices from one remote is a relief. Download a remote control app, such as iRule and then sync your phone to devices including your Xbox One, Roku and Apple TV.

If you have smart light bulbs, you can sync your phone to those as well. Follow these tips on how to turn your device into a universal remote so you never have to wonder where your TV remote is hiding again.

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Turn your Android phone into a Google Home

Repurposing your Android phone to be a Google Home smart speaker is simple and requires no app downloads. Make sure your phone is updated to the latest Android OS so you have "OK, Google." Next, you'll need to find a Bluetooth speaker to pair your phone with. Make sure both devices stay plugged in and on at all times. You'll be ready to give Google commands in no time. The best part is you won't have to spend $129 on a Google Home. Learn more about what you can do with a Google Home here.

Your Android can double as a home security camera

Feel secure by turning your old phone into a home security camera. Download a security camera app, like Alfred (can also use with iPhone) to get started. Check on your house while you're at work to make sure all is well. Place the phone in the main room of the house in a spot where you have the best view.

When you're home, set it up outside (hidden, of course) to see who's knocking on your door or to see any suspicious activity. Maybe you'll find it's just a raccoon that's been leaving candy wrappers in your yard and not your neighbor's kid.

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Use your old phone as a baby monitor

Instead of running into your child's room every time you think you hear crying or a strange noise, check to see if your baby is OK by turning your old phone into a baby monitor.

You can set your old phone up in the room and access it from your current phone by installing Skype on both devices. You can also use a baby monitor app like Dormi. We haven't tested them on real babies, but the customer ratings are excellent. You'll feel better knowing that you can be in any room and still see your baby.

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Turn your Android into a wireless mouse

It can be annoying when your wireless mouse dies on you with no warning. It helps to have a backup, and you can turn your phone into a mouse in no time. You'll need to download an app, such as Remote Mouse, in order to do so.

Once you have the app, connect your phone and desktop to the same Wi-Fi network and say bye-bye to that old-school mouse. Keep it in your laptop case for when you're on the go and stop by a coffee shop to get some work done.

Keep your old phone as a music player

Free up storage space on your new phone by using your old phone as a media player. Since you have a new phone, you can wipe all the data off your old phone (except your music and music apps).

You'll be able to add as many songs as your old phone will allow without worrying about how much storage you're using. Hook it up to your surround-sound speaker if you're having a party and let the fun begin.

The great thing is you'll be able to leave it in one place and won't have to worry about incoming calls and messages interrupting your tunes.

Now that you've got some cool new ideas for your phone, here's how to cast and mirror an Android screen to a TV, how to disinfect your device without damaging it and how to set up Google Pay on your Android.