Debate: How many cameras should a smartphone have? What type and why?

I would say an ultra wide camera ( there should be an option to switch from ultra wide to wide) and a telephoto!

I always like to have a good ultrawide, standard, and zoom lens. I think this gives the vast majority of users the ability to take good pics in the vast majority of scenarios. Need to get a good landscape shot, the ultrawide is there and it can also double as a really good macro cam if the manufacturer tunes it correctly. And a good zoom cam removes the issue with having to compensate for the lack of it with really high resolution and digital zoom. And a good standard cam for all the usual scenarios. And we need good night camera shots as well. Nothing too fancy, but well rounded.

I can say. The Standard Camera, The Ultrawide Camera, The Zoom Camera, and Flir Camera.

Wow...that Nokia 9 is fetching a pretty penny on Amazon and eBay. From $400 to $700. One person is listing for $1500 on ebay

I am an electronic engineer not an optical enginner but i will give this a shot and please forgive any technical ignorance i may exhibit. If you include the front facing camera (selfie), which I believe should only be retailed for video calls as i am anti selfie, four. A main camera with around a 25 to 35mm focal length, ~1.6 aperture and >50mp for normal every day shooting. An optical zoom camera with a minimum of 10x optical and a maximum of "as high as you can get without destroying quality", as low of an aperture as reasonable, a focal length of between 60 and 250mm and with a >30mp rating. The third an ultra wide an aperture size of ~f2.1, a focal length of between 10 and 15mm and around a 15mp rating. All cameras should have a sensor size of around 1/3.x. I arrived at these specs by reviewing as many of the top rated phone cameras I could (within reason) and reading how most people tend to utilize and review these cameras. Of course, as I stated in mu opening, I am no expert and am just trying to digest and collate all the data I gather. I belive phone cameras are great for convenience photos and will never really replace high end DSLRs for professional use.

So you can zoom in closer and the shot will still be clear.

It is possible to have a single camera that does what three do. However, based on some responses here, the more cameras, the better, just because. And this is why we cannot have nice things.

I hope to see a day where we will only have 1 main powerful high resolution camera sensor with at least 100 degree FOV which can act as ultrawide, wide and 3x zoom for portraits. I'm pretty sure this is possible given that we have 200MP cameras already.

The future of mobile photography is 100500+ camera modules that are located on the entire back surface of the phone. Those users who cannot afford it will use Chinese inexpensive phones (iPhone and others).

they need 2 high quality cameras and this will probably where are we heading. It could be done in 2-3 years but that would mean phone cams peaking so they will milk us for another 10-15 years to that point for sure.

1 Inch quality cam with ultrawide lense that can replace the main cam and go to 2x without losing any quality.

1/1.2 inch variable zoom camera from 3x to 7-8x that can give up to 20x quality pics without losing any quality.

These cams will cover all scenarios and realistically they have enough space to put them in a phone.