A wearable: No one does it superiorly better than anyone else.
Fitbit, basis, apple watch, pebble, android wears, moo (or something?). There's a long list. To see what it might be like; you can probably download an app that step-tracks via your phone's gyroscope. There is a limit to the usefulness and really it depends how much you pay attention to it. I found the notifications to be unmotivating to get me to move, but that might be different for you. Each system is trying its best to be the best.
The biggest factors seem to be:
A new rule for myself when quantifying: have a purpose in mind before gathering data for data sake. Its great to track skin perspiration but without a purpose for the information, its as good as not tracking it.
As for burn rates due to exercise, look into MET's, Base metabolic rates and caloric intake. You might be surprised with the difference between exercise/not to weight loss. (Important note: the benefits of exercise extend beyond weight loss. You should exercise for all the benefits of improved health and decreased chance of disease)
A new rule for myself when quantifying: have a purpose in mind before gathering data for data sake.
From doing a lot of different QS myself and talking with other people about it, I think that's a key point. You actually have to care. If you don't care about what you are measuring you are unlikely to get any return.
This is the public group rationality diary for June 22th - July 11th, 2015. It's a place to record and chat about it if you have done, or are actively doing, things like:
Established a useful new habit
Obtained new evidence that made you change your mind about some belief
Decided to behave in a different way in some set of situations
Optimized some part of a common routine or cached behavior
Consciously changed your emotions or affect with respect to something
Consciously pursued new valuable information about something that could make a big difference in your life
Learned something new about your beliefs, behavior, or life that surprised you
Tried doing any of the above and failed
Or anything else interesting which you want to share, so that other people can think about it, and perhaps be inspired to take action themselves. Try to include enough details so that everyone can use each other's experiences to learn about what tends to work out, and what doesn't tend to work out.
Archive of previous rationality diaries
Note to future posters: no one is in charge of posting these threads. If it's time for a new thread, and you want a new thread, just create it. It should run for about two weeks, finish on a Saturday, and have the 'group_rationality_diary' tag.