Xcode Navigation

  • cmd + shift + 2 - open organizer
  • cmd + option + return - show assistant editor
  • cmd + return - show standard editor (hide assistant editor) 
  • cmd + shift + o - quickly open or jump to a file
  • cmd + ctrl + up/down - switch between header and implementation file
  • cmd + ctrl + left/right - navigate to previous/next file
  • cmd + click - jump to method declaration
  • option + click - open quick documentation

Inline

  • ctrl + spacebar (or escape) - show code completion suggestions
  • ctrl + a + k + k - delete line
  • cmd + ctrl + e - rename variable in scope
  • cmd + f - open find bar
  • cmd + option + f - open find & replace bar
  • cmd + e - copy selection to find bar (without copying to clipboard)
  • cmd + g - find next
  • cmd + shift + g - find previous
  • cmd + ] - indent
  • cmd + [ - outdent
  • cmd + / - comment/uncomment current line
Also, just stumbled across this great info graphic created by Robert Saunders