Don't. Smartphones are not a good idea, Tor broswer or Onion Browser or whatever the fuck. Just don't. Maybe to browse the forums as a guest and maybe even login to the main site using a dummy account.. but under NO circumstances should you log into your real accounts via your smartphone. Trust me. Have some patience and wait till you're back at your PC/Mac. You want to be the first guy that gets in trouble buying MDMA on your fucking iPhone? Don't be that guy.