Phone cameras are awesome these days, but they have their limitations.
I'd be more inclined - if self-shooting - to invest in a proper camera and use the phone as a remote. Set the camera up on a tripod, link the phone app, and use that to release the shutter. With a shutter delay, if need be and you want all of you in the shot, rather than contorting to reach the phone.
Nor would I limit myself to a DSLR. I have good Leica, Sony, Olympus and Canon units, and they are all mirrorless.
One of the major problems with using a phone to shoot nudes is lighting. A phone will have an internal flash, but that only goes so far, and may not give you the skin tones you want.
A "proper" camera will be able to fire a flash that isn't aimed along the axis of the shot, and can be set up remotely or bounced off reflective surfacers to give a softer light, which is often exactly what you want wen shooting nudes.
And then there's post-processing. Getting it 100% right in the camera can be tricky, but post can save a lot of shots.
Britni, who likes shooting raw