I don't understand the authors choice to limit himself to Apple or Google. You've been able to do development on Linux notebooks (and Windows notebooks, of course) since decades. I can absolutely recommend Dell (and ThinkPad, though not from personal experience) notebooks with Ubuntu preinstalled/officially supported. Or is the question if a Chromebook is en vogue to use this season at Starbucks?
I use my Arch Linux T450 Lenovo laptopand it's a beast. $500 on eBay + $180 for SSD + $150 for RAM.
My laptop has 20Gb of RAM, 2x 1Tb SSDs, and 10 hours battery life, with 1 hot swap batteries pushing me to 18 hours battery life if I want it. Total cost: ~$900 with tax and shipping
IMO best track pad outside of Apple + best laptop keyboard
Interesting. Do you know if T450 Lenovo supports the hack I use with https://github.com/avibrazil/RDM? I use my 13" macbook pro with a 2560x1600 resolution because I enjoy the larger screen space. IMO this the killer feature.