If you're willing to spend the money, look into the Samsung galaxy or the Iphone series. Personally, I have a Galaxy s4 and it takes great pictures and does everything I want it to. If your not willing to spend a lot of money, The nexus 5 or the Samsung s3 will do the trick, low price, and gets the job done. If simplicity is a factor, the Samsung series has an easy mode, and the Iphones are pretty basic.
I have used all brands of phones from Motorola, Sony, Nokia, Samsung etc. Sony has the best camera and you don't even have to do anything just snap the pix. S4 is great too but it produces better pix taken in the dark, bright day light not so much. IMO S4's best feature is its GPS combined with Google Maps. I don't mean to offend iPhone fans, but it is not that great, especially for its price.