How to get genuinely free Android apps and free Android games

On your phone or tablet launch the web browser and head to amazon.co.uk/underground. Tap the button to Download Amazon Underground and the app will begin downloading to your device.

A pop-up will appear at the bottom of your screen that says: 'This type of file can harm your device. Do you want to keep Amazon_App.apk anyway?' Tap OK, and the app will begin downloading to your device.

Because you aren't downloading the Amazon Underground app through Google Play you first need to instruct your phone or tablet to allow you to install software from unknown sources. You'll find this setting in Settings, Security, Unknown sources, and by default it will be disabled. Toggle on the setting, then accept the warning that third-party apps may harm your device (you're fairly safe with Amazon).

It's a good idea to return to this setting once you have completed this walkthrough and disable it, thereby protecting yourself from any future dubious downloads that come your way.

Once the app has finished downloading to your device, either drag down the notification bar at the top of the screen and tap on the download, or find and tap on the .apk file in your Downloads folder.

As with any other app you download to your phone or tablet, you'll be asked to accept certain permissions before the app is installed. If you already have the Amazon shopping app on your device (which Amazon Underground replaces), the New permissions tab will be empty. Amazon Underground requires no extra permissions over the original Android app, and you can see which permissions that requested by selecting the All tab.

If you're happy to continue, tap Install at the bottom right of the screen. Once the app has installed, click Open.

Amazon Underground looks just like the usual Amazon shopping app for Android, but there's a new item in the menu. Having signed into your Amazon account, tap on the three vertical lines icon at the top left of the screen and hit the down arrow next to Apps & Games. Now choose Underground Apps & Games.

Any apps and games listed in this section are completely free, with no hidden in-app purchases. You can also spot these apps by their 'Actually free' banners.

Browse Amazon Underground for an app or game that takes your fancy. We chose to download Frozen Free Fall, which includes free items and levels that would otherwise incur a $31.87 charge.

The installation process is very similar to that of Google Play, so should feel familiar. By default Amazon Underground won't allow app downloads bigger than 50MB unless you're connected to Wi-Fi (you can change this in the settings). If your Wi-Fi is on or the app is less than 50MB, simply tap Install, accept the permissions and the app will download to your device.

It's worth taking a quick detour to the Settings menu even if your Wi-Fi is on, since Amazon Underground won't by default have the same safeguards in place as Google Play might on your device.

Open the main menu (tap the three horizontal lines icon) and this time choose Apps & Games Settings. Here you'll find settings to disable in-app purchases (apps downloaded through Amazon Underground won't have these, but other non-Underground apps downloaded from Amazon likely will) and to engage parental controls.

Read next: Amazon Prime Instant Video vs Netflix

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