Buckner is based in Minneapolis and was one of the first accounts (under the username 'intao') I ever followed on Instagram. There's a remote, isolated, other-worldly feel to many of his images that I love.
Sheldon is a Canadian street photographer, now based in New York. Shooting almost entirely street photography on a phone, he won the 2014 Mobile Photographer of the Year award. Another great Instagram account to follow too.