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Currently you can see what number you are ranked among the players of is world. When you tap the ranking though this wont open as yet until the full global ranking is released. When available, you will be able to view all players on the same world.
this number tells you how many free population you have. If you tap here, it will open a small window telling you what total population is, and how much free population you have a able to use.
Next along is the smiley face - you want to keep this gold all the time, as this means your townspeople are enthusiastic which gives you a 120% boost your productivity. All coin and supplies buildings will produce more, and when you fight you will receive more points also. Again, tap the face for more detailed information.