Carphone Warehouse recently launched its own mobile network, called iD. The UK retailer has also released a companion app for Windows Phone, enabling customers to manage their accounts while on the move.
With the app installed, those subscribed to the iD MVNO will be able to manage their accounts and make payments. Bills from the past six months will be available for viewing and bundle extras are also accessible for purchase. If you believe you're eligible for an upgrade, the iD app can also confirm whether or not you're due a new smartphone.
It's worth noting that the app does not currently support business customers. Give it a go if you're with the network and let us know how you get on.