The stumbling-block to using a phone as an all-in-one solution for photography is basically that the lenses aren't as good as those on any dedicated camera. While you would expect a DSLR (Digital Single Lens Reflex) camera to sport a better lens, even the most basic, sub-hundred-dollar point-and-shoots have higher quality glass than the best phones.
Manual adjustments for exposure and other settings like white balance are also missing on many smartphones, as is an optical zoom that provides higher quality close-ups than a processor-driven zoom.
However, there are two things the smartphone, resplendent with camera, does offer. One is a seriously powerful computer processor -- much more so than any camera's -- and the second is filter- and editing-style apps -- tons of them.
My solution to...