Update: 3rd March, 2022. The app. has just declared a new version is available, sent me to download it, & promptly told me the update isn't available in my region..? Had to use the website to top-up as the app. won't log-in due to this elusive update. Previous review points still stand, five years later, balances still take a ridiculous time to load. Service still frequently doesn't work on weekends & when the website is also down. The payment page is better formatted though... if you see it.
E.ON Energy at Google Play market analyse