I am in no way affiliated with the company Sweatcoin, but as someone who is putting a significant amount of energy into staying fit, I feel compelled to share my thoughts on this novel app.
I have been using the app for almost a week, and it is amazing to me how just knowing it is running in the background has motivated me to do more walking and running. As I have learned from other blockchain apps, like Steemit, even very small financial incentives have a tangible influence on motivation. I think the key here is that if you already have a desire to develop and sustain a regular practice of some sort, like walking/running, or writing, then a micro incentive like making a few cents or more has an effect.
So the basic idea of Sweatcoin is that it runs in the background on your device so that you don;t have to remember to turn it on when you begin walking or running. In its current state the app will only work outdoors, which has something to do with the complex algorithm used to verify that you are actually walking and not riding in a car, etc. Because I am always cynical, I searched "sweatcoin hack" the other day and found some interesting information. First, if you are a cheater, keep in mind that websites offering a hack might be malicious. From there, you can obviously do things like ride a bike slowly (questionable whether or not this is even against Sweatcoins policy, as it is exercise), or let your friend carry your phone while they walk or run. I guess such practices could compromise the success of the project, but I have a feeling the developers are going to keep tweaking the verification process of your logged steps to rule out cheating (i.e. seems like it would be fairly simply to detect that two phones are logging the exact same route at the same time).
But on to the positive.
As you can see, I have logged 46,000 steps, and that has been converted to 49.56 Sweatcoin.
At my current rate of accumulated Sweatcoin, I might earn enough to exchange them for something like $50 Amazon gift card in one year.
I am cool with that, especially if I am earning that $50 by doing something I would already be doing for no incentive, and this goal might actually encourage me to walk and run a little more. As an example, I am a high school track coach, and that means I spend most of my Saturdays in April, May and part of June at all-day meets. Yesterday I didn't sit down once, and instead took walks around the stadium and fields when I wasn't actively coaching my kids. I ended up accumulating over 10,000 steps for the day, and earned 10 Sweatcoin. It is also with noting that I am usually quite fatigued after such days, but yesterday I felt great when I got home, and I really, really enjoyed a frosty beer with zero guilt!
I am not posting this to make any money, but if you want to use my code below go for it. I am a coach with 
Cheers!