I started poking around w/ mitmproxy the other day as well, since I had started to get a little tired of waiting (Microsoft has promised an open API/SDK of some

I started poking around w/ mitmproxy the other day as well, since I had started to get a little tired of waiting (Microsoft has promised an open API/SDK of some sort, but there haven't been any updates to any of the software since release) w/ similar results. (I did this against the iOS app). So I'll just post a couple notes: * auth appears to be using OAuth WRAP (deprecated as a spec, but Microsoft appears to use it for Live logins), so I'm sure could be pretty easily extracted for an API library * As mentioned the API mostly talks to an endpoint on and the returns are gzipped JSON except for a PUT to prodwus0sts.blob.core.windows.net for the binary log of your actual data (there's a subsequent PUT that then sends the UploadId and some other metadata to the API server) People have mentioned wanting to avoid sending your data to the cloud completely, and that should be completely possible. The easy way atm is that you could just mitm the endpoints and sync as normal w/ the app. However, there are at least a couple of people that have successfully reverse-engineered the BTLE protocol, although I haven't seen anything fully published yet. This appears to mostly/primarly be based on digging through the Windows client's DLL. Pic of source w/ some of the BT protocol: https://twitter.com/JustinAngel/status/527955001436418048 https://twitter.com/JustinAngel/status/527955001436418048 Some BT functions: https://twitter.com/JustinAngel/status/528383467742957571 https://twitter.com/JustinAngel/status/528383467742957571 Methods extracted from the dll: https://twitter.com/JustinAngel/status/529876592479047682 https://twitter.com/JustinAngel/status/529876592479047682 (On OSX, strings gives you significantly less useful information, although apparently it was built by 'ianhowle' and there's a native Objective-C "CargoKit" library) Note, there's one open source project that has theming and plans on building live sensor output: http://unband.nachmore.com/ http://unband.nachmore.com/ And there's a closed source phone already that does access all the sensor data in realtime: http://www.windowsphone.com/en-us/store/app/band-sensor-monitor/68f97b41-de2f-4579-a473-5d476a5c5196 http://www.windowsphone.com/en-us/store/app/band-sensor-moni... I'm not too familiar with Windows Phone, but I believe you can access and decompile an unencrypted XAP if you have a rooted Windows Phone to see what it's doing. I don't really have much experience/use/access to Windows stuff in general, but for someone w/ that kind of experience, I can't imagine it being very hard to deconstruct.