App Backup is a free utility tool developed by Train your Brain for Android devices. As the name suggests, it is designed to backup and extract APK files to the SD card, making it convenient for users to share installed and backup files with just one tap.

One of the standout features of this app is the multi-selection option that allows users to backup, share, install, and uninstall APK files in one go. Additionally, users can backup APK files to Google Drive, Dropbox, and other third-party applications. The app also allows users to extract and retrieve APK files to the SD card automatically, which is a great way to free up phone memory.

App Backup also offers a search tool for backup and installed apps, making it easier to manage APK files. The app shows the backup taken time and APK size in the list. Moreover, users can downgrade app versions if they dislike the updated version.

It is important to note that App Backup cannot backup or restore data or settings of apps, it can only backup and restore APK files. The app does not require root access and the requested permission to read the SD card is used to modify or delete the contents of the SD card to read and write APK files.

Overall, App Backup is an efficient and useful tool for Android users who want to backup and share their APK files with ease.