Hello, I am looking for a device to be in communications with another person while skiing without having to push a button. Exactly like a cell phone, but since phones don't work up where we ski looking for something else.
What you are looking for is a walkie-talkie / two-way radio / private mobile radio with voice control.
Normally, to communicate with a walkie-talkie, you need to press a transmit button. Some models, however, have voice-control: they will automatically start transmitting based on voice input. My friend and I used the Midland G7 XTR, that includes this feature. We did not use the voice control, so I don't know how well it works. We were quite worried about battery lifetimes, and wanted to prevent our walkie-talkies from transmitting without need (there are other sounds in nature besides our voice). In principle, though, walkie-talkie with voice control should be exactly what you need.