Granite OS? Where is the source? If the answer is "private", then that's not good enough for something selling itself as a security product in 2015. It's hard

Granite OS? Where is the source? If the answer is "private", then that's not good enough for something selling itself as a security product in 2015. It's hard to find anything real about this phone. I hate these "growth hacked" minimal websites - impossible to find any actual information. Are they really expecting me to buy $800 worth of phone on the information they're showing me about it on that page? Why am I supposed to trust them? Do they take me for a complete idiot?