The camera is. If sunset sun rays don't damage it, I'd think it'll handle corona rays just fine.

OP, the image on the phone's screen can't hurt your eyes. It's just light generated by the LEDs in the screen. I'd face away from the sun, remove my eclipse glasses, and frame the image on the phone using its front (selfie) camera. Make sure to put on the glasses again when you face back to the sun, and don't let the goal of photographing the event distract you from experiencing it yourself.