Gosh Dan...your soft side makes me melt.
I know those apps but I'm happy to have found an official assignment with a regular pay. Often those app walkers are self employed or unofficial. I have at least a bit of a security if something would happen being employed.
If Pura is into dog walking then go ahead! It doesn't have to be the big ones or youngsters. Even old dogs appreciate someone taking them out and then it is not as stressful in the beginning.