Day-O 2 is a dead simple tab bar app that serves one single purpose. Replacing system menu bar clock with a quick, month-view calendar. Even Calendar or Fantastical takes time to load, Day-O doesn’t, due to its simplicity. Day-O 2 come in very handy if you are on a call and want to check the calendar. It was supposed to be that easy. The new version now supports dark mode and transparency.