Does the Wahoo unit turn your phone into a HRM?
Dunno about wahoo, but there are apps that will by using the camera on your phone. I tried it but thought it's useless, you can do the same thing in the same amount of time by counting your pulse. This sorta holds my attitude toward all the exercise related plans/gadgets, human managed to stay fit for thousands of years without them, why start now.
I am somewhat of a minimalist when it comes to exercise accessories, but I have to disagree with you. Some gadgets allow you to have more accurate information and deliver it with less intrusion into your workout.
Take an HRM for example. I can lift my wrist and know in a glance if I am in my target zone. To take my pulse I have to stop what I am doing and hold still for ten to fifteen seconds while looking at a clock or watch.
Another example is a bike computer. After riding for a few years I upgraded to a unit that had a cadence function. Why would I need that? I had been riding in excess of 2000 miles per year. Surely I could tell how fast I was peddling just by intuition and experience. After having the new computer I found out that my perception of my cadence was off by up to 10 rpm.
As for humans staying in shape for thousands of years without any plans/gadgets, well, they didn't need them because life made it unnecessary. The worked very hard ever day at just staying alive. They didn't need motivation or knowledge about their bodies to keep fit. Today on the other hand we have not only the opportunity to be sedentary, but are required by our jobs to be sedentary for a good part of every day. We need a plan to get and stay healthy. The gadgets we use make our plans and our exercise routines more effective and more enjoyable.
But, as usual, its a personal matter. I like gadgets, you don't and we are both better off for exercising and striving to be more fit.