GO is a mobile application for Android devices that allows users to manage their mobile numbers, bills, top-ups, and bundles. The app is free and offered by GO plc, a company based in Malta. With GO, users can easily view their services and switch between them, add cards for instant payments, and top-up their own or their friends and family's GO numbers.

Pay Monthly customers can link and view their bills online, settle bills directly through the app, view their payment history, and add mobile bundles to their monthly bill. Pay as you GO customers can top-up directly through the app, view their current top-up balance, view their top-up history and receipts, and add mobile bundles from their top-up balance.

The app also comes with a built-in tutorial system for all features and provides all the contact information users may need to get in touch. GO is a secure and intuitive service that won't use up data while on the GO network, making it a convenient and practical tool for managing mobile services on the go.