Alice Thiu poses for a portrait with her custom-made bike from her bicycle company THESIS at Crissy Field in San Francisco, Calif. on Friday, October 12th, 2018. (Mira Laing) More pictures on this subject...

Boosted boards are modeled on the floor of Black Diamond Sports in Palo Alto. (Colin Blake/ Xpress)   By Colin Blake A skateboard is a very analog form of mobility in that the rider is responsible...