Toting around a big tele and tripod for an iPhone makes no sense...bring a body too.
On the other hand....the ones that just snap on and will fit in a pocket or purse are a good thing IMHO as the truth was posted above, the best camera is the one you have with you.
If I'm going out to shoot pictures I will have film and decent optics, usually German, and generally a proper tripod.
When I'm at work or running down to the shops or out on the bike then I don't have a bag of my good expensive cameras with me but I always have my iPhone and there is a compact pocket digi that always leaves the house with me because it fits my shirt pocket and I hardly notice it's there. Also because I am yet to find a Hapyucc and a source of 16mm film....
Some of my best photos were taken on the pocket digi simply because it was in my pocket when an unmissable shot popped up when I was at work or on the way to the supermarket and even when I've been out with real cameras there have been fleeting images that would be gone before i could get a film camera out of the bag, but in 5 seconds the pocket cam is in my hand and fully powered up for a quick shot.
To get a good photo first you have to get A photo in the first place...
There is no doubt though that given the choice I will take a photo through Zeiss Ikon, Schneider, Hexanon or Fujinon optics on some lovely film....