I'm really excited about the 'small linux computer' in your pocket concept. This isn't a new concept of course and it's basically a raspberry pi (arm64) 'phone' that connects to an external monitor in 'convergence' mode. It's blissfully everything the iphone isn't! https://pine64.com/product-category/pinephone/?v=0446c16e2e66
Here are some preview product images.