Quick answer
Your home screen shows your days remaining. Use Book to request leave, Mine to see your requests, and Calendar or Wallchart to see who else is off.
Find your way around
The bar along the bottom is your menu: Calendar and Wallchart show who is off, Book requests leave, and Mine lists your own requests. Your days remaining show at the top.
Get your leave in Outlook
If you use Outlook, tap Connect Outlook so your approved leave shows in your own calendar as Out of Office. It only adds your leave; it does not read your calendar.