Google has revamped the sideloading process on Android devices with a new protocol called "Advanced Flow" to enhance user security while allowing the installation of applications from downloaded APK files. Users must enable sideloading, authenticate their identity, and confirm they are not being pressured into installation, followed by a device restart and a 24-hour waiting period. Users can choose to allow installations for seven days or indefinitely. To sideload apps, users need to download an APK file, disable Advanced Protection temporarily, install the app, and then re-enable Advanced Protection. Caution is advised when downloading APK files from unknown sources, with recommendations for trusted sites like APKMirror, F-Droid, and Uptodown.