I have written a little android app that can get the heart rate and pedometer data stream from the Microsoft Band 2. Now instead of using a smartphone, I would like to do the same thing but now use a raspberry Pi, so that I can further process the data. Is this possible and if so, how exactly should I do this?
Yes, you can install Android on a raspberry Pi, you just need the image of android built for raspberry pi. Here is a tutorial: https://www.squirrelhosting.co.uk/hosting-blog/hosting-blog-info.php?id=22
Also, searching for "Android on raspberry pi" on google show a lot of info, you should check more tutorials.
Tip: Android can´t be Hardware accelarated in Raspberry pi, so anything that uses UI will be a lot slower than when running on a device.