Building your application onto your phone

1. Go over the blocks of your project once again, making sure there are no errors or warnings. If you find missing sockets or detached blocks, either delete them or fill them.

2. Navigate to the Build section, and choose APK as the build function. APK is the standard file for Android apps, allowing you to download your app on your phone or redistribute it. AABs are only for the Google Play Store.

3. A progress bar should pop up on your builder. Patiently wait for AppInventor to build your app. The time taken to build your app depends on your project size, which includes a lot of factors. (e.g. blocks used, screens used, assets used, etc.)

4. Once it's done, it will show a download button and a URL download QR code. 

• If you are installing this file on your phone or with a group of friends present, then scan the code and proceed to the following steps. Note that the link is only valid for two hours before it is unavailable, so be quick.

• If you are sharing this file with the public or targetting a large audience, download the APK on your computer, upload it to a file-storage service (such as Google Drive/GitHub), and share the link provided by the service instead. 

5. On your phone, open a QR code reader and scan the QR code. Redirect to the result link into a browser, and download the file on your device.

6. Open the file after the download process is complete.

7. If this is your first time using this browser to download, then you will be disabled to download the app by default. This is because Android has a defense-mechanism against apps from unknown sources, which potentially contains viruses. Your app is not downloaded from an app store, so it will show this message. However, AppInventor does not produce viruses (unless if you intentionally injected one), so it is safe to say that your apps are secure. Allow the browser to download apps from this source.

7. Install the application in the installation dialog. 

8. Done! Your application is complete, and you can open it like any other applications. You can click on the Open button in the dialog, or navigate away and find your application icon along with other applications.