We don't do any ARM builds yet. It uses the same C++ backend we built for our file transfer application which runs on iOS and Android so it shouldn't be too hard for us to get it working on a Raspberry Pi.
Alright, good to hear that it is within reach. In our startup what we want that we can't get from Dropbox/Google is privacy. I've been looking at owncloud which would give us privacy but redundancy seems complicated and therefore my excitement about you guys. The possibility to start out super cheap with two RasPi3 and external drives and in the future migrate to more scalable solutions like S3 would make this product pretty awesome for everyone from home tinkerers to enterprises.