British Gas Energy is a utility app developed by British Gas Trading for iPhone users. The app is designed to support millions of customers already on their new system. Users with account numbers starting with 'A' or 'BGX' can seamlessly transition to the new system and start using the app immediately. For those with account numbers starting with '85', the app will notify them when they can switch over.

The app offers features such as tracking energy usage (requires a smart meter), checking account balances, making bill payments, viewing billing history, setting up Direct Debit, changing tariffs, submitting meter readings, managing multiple energy accounts, and utilizing Light and Dark Mode, fingerprint, and face unlock. It also includes the PeakSave feature to help users save money.