This is not a new app, but it´s worth to bring it back. Member danielherrero created a cab that has proved to be very helpful to easily change between WCDM to GSM and vice versa to save battery.
This application works on newer devices such as the HD2.
Originally posted by danielherrero
My battery drains very quickly in my area (HSDPA). But if i force GSM then the battery lasts two or three days and i only need hsdpa 3 or 4 times by day, for example
1) Compatibility with new Bluetooth Widcomm stack (HTC Touch Pro2, HTC Touch HD2, etc);
2) Compatibility to switch band with HTC Touch HD2
3) Compatibility to switch band with Toshiba TG01
4) switching is faster because now I dont turn radio off, just unregister and register from network. No need to enter automatically PIN code too.