Read the paragraph "#2 Do mobile first. Like, really do it."
   We do lack processing power on mobile, so for that
   2-3billion people, who are using mobile _only_ or
   mobile first, we need economical solutions.

Or use an older, 'underpowered' (by modern standards) machine for development, like I do. A Thinkpad T42p will give you a 1600x1200 screen, one of the best mobile keyboards available, 5-6 hours of autonomy with an extended battery and... the awesome power of a 1.8 GHz Pentium M... well, not so awesome maybe but if it works on that machine it flies on anything more up to date.