Different smartphone makers focus on different aspects of the camera - to decide on the best camera phone for you, you need to look at the camera strengths, available modes and the shooting experience itself.
The camera strengths involve what the device focuses on (pun intended) - some have long-ranging zoom cameras while others have high-res sensors or dedicated macro lenses. You need to ask yourself what kind of pictures you want to take, and find a phone that caters for that, or opt for an all-rounder if you're not sure.
The available modes might help, as most brands create their own camera modes to give you an edge. Samsung has Single Take and Food, both of which help you take great-looking pictures with little work, while OnePlus and Oppo have some Hasselblad-created ones, and Xiaomi often throws weird curveballs like Sky which lets you change the weather in your photos (really!).
Finally, the shooting experience could influence your buying choice. Some phones offer and easy point-and-shoot experience, so that at the tap of a button you can take social-media-ready posts, while others have a more involved process that makes it easy to fiddle with different settings. Your choice here will depend on your comfort level with cameras, and we'll definitely note anything pertinent in our reviews.
Of course, you need to consider the rest of the phone experience in your choice too - a phone is for life, not just for photoshoots. So bear in mind your budget, the size of phone you want, and whether it's a good device or not.