I've not heard about this app until today. The reason for me calling Three technical support was to blag a 3 Home Signal which is a device that connects a Three phone to their network using broadband.
Anyway, Three inTouch is their app for connecting iPhones (not 4) and Android phones to their network over wifi. This is really useful if you live in a house with a low mobile signal (or no signal) and sometimes miss calls.
It's easy to set up. Download & install it, then disable wifi and open the application. Accept the terms & conditions and then click activate. Job done. on iPhone disable mobile data when in the house, then enable it when leaving.
I can't test the app because I get a decent signal at home, but family and friends live in marginal areas. In particular I recommended three to my parents because of the excellent 321 pay as you go service, but their signal isn't really reliable enough due to the transmitter location.
Obviously more or less everyone reading this on here will already use apps for messaging like whatsapp, but this Three inTouch is going to be great for receiving and making calls.
Here's some info: [Only registered and activated users can see links. ]