title: How can I see that a real world time has passed from a stored start date in obj-c/ios?
body: <p>In my game players will be able to plant a tree, which will take 3 hours to grow. When the player logs back in how would I calculate whether that tree is now fully grown? the creation date of the tree (planted) will be stored on a server, and I will be storing the 3 hours in seconds (not sure if that should be an int of NSNumber) also on the server.</p>
  
  <p>Thanks for any help.</p>