Portable self-diagnosis equipment is kind of a double-edged sword. From one side, it can help a lot of people, but from the other side, people can think they don't need to visit a doctor, because this equipment can diagnose them. I think such devices should be used with high caution and under doctor's control. Like in case you need to control your blood sugar, stuff like that.
we already have blood pressure measuring devices. these aren't a stand in for doctors ,but are good to check if you need to go to the doctor. same for self-diagnosis devices.
Measuring blood sugar levels, heart rate and so on can easily be done by yourself. It's the interpretation that sometimes requires a doctor.
Yes, there are some stuffs to check our own health to get our own analysis. And if we felt something bad based on it, we should go to the doctor for further treatment.