I am still hopeful Linux is the future of mobile devices. I really dislike that on android 5 years of feature updates is really good and only the best phones can strive for this, where as a 10 year old laptop or desktop computer can usually run Linux without any problems and expect both security and feature updates as long as you want. Not even mentioning the limited choice in software that works in an android environment.
I currently use Sailfish which isn't what most people mean by mobile linux and does have a lot of problems, but hopefully my sailfish device I have now will see me through until mobile linux is at the point I feel like I can move across.