Quantifying yourself without giving it all away

One new project just cropped up in my mind: I’d like to quantify myself more. You know, keep track of my sleeping and moving patters so I can learn and improve them.

But all the stuff I find online, by Nike or by Fitbit, requires you to register online and compare results and blah blah blah; send all your data all over the place and god knows where!

I don’t want that! If I have to pay a steep €100,- for some plastic wristband I don’t want to pay again with my data. So, where are the privacy aware self quantifiers?

Looking forward to hear from you.