With so many amazing apps on Android, iOS, and Windows Phone, it can be tough to keep track of everything that you've downloaded. If you often download apps to test-drive them and then forget about them, you might forget to put them on a new phone when you get one.

Fortunately, every mobile platform keeps a list of apps you've downloaded, letting you know whether you've tried one before — and more importantly, letting you download it again for free! Here's how to find that list on each platform.

Android

On Android, open the Google Play Store app and tap the hamburger menu (three bars) on the upper-left corner of the screen. Choose My Apps and Games to view your installed apps, and scroll over to All to view everything you've downloaded, starting with the most recent.

Remember that if you're on Android, there are awesome apps that aren't in the Play Store, so don't forget to check those out, too!

iPhone and iPad

For iOS, open up the App Store and choose the Updates tab in the bottom-right of the toolbar. Next, select Purchases. You'll be greeted with every app you've downloaded to your phone, as well as those that you own but aren't currently on your device.

If you think you're missing something, tap Not on This iPhone to view owned apps that you don't have installed yet.

Windows 10 Mobile

Running Windows 10 mobile? Open the Windows Store, then click on your profile picture icon. Tap My Library to open to check out all your currently installed apps. Press Show All if you'd like to review everything that you've downloaded with your Microsoft account.

Need some great apps to fill up these lists? Check out the best iOS apps of last year.

What apps did you re-discover by checking your downloads? Let us know what your favorites are down in the comments!

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