1. How to install Île-de-France Mobilités APK/XAPK file?
APK file: Tap on the downloaded APK file, and follow the on-screen prompts to complete the installation.
XAPK file: It's a compressed package containing an APK file and additional data files. You need a XAPK installer to install it. If you're using MEmu Android Emulator on PC, simply install the XAPK file directly into MEmu.