Which format?
Probably none.
I am lucky enough to have several cameras. So I treat the camera like a tool in a tool box. I select the camera and lens to use based on what I am going to shoot, and how I want to shoot. I don't shoot football with my P&S, nor do I take my view camera on vacation.
When I was younger, I used to be a 35mm SLR snob.
Then I learned, that being a snob costed me MANY lost pictures. This was because the SLR was not easy and fast to bring into action around the house, so many "photo ops" were never shot. That is where a small P&S (or Instamatic) would have worked much better.
After that bitter lesson, I try to be more objective in camera/lens selection. Different cameras have a place in the kit. Having a "favorite" will bias the selection, and it may not be the most appropriate selection.
Having said that.
For many people it is the phone camera, because it is more available than any camera, as many people live with their phone within arms reach. And the Image Quality you can get out of them is fantastic, so why carry a P&S camera?