The is your standard "build & grind" game, not unlike those on Facebook. You build, you wait, you collect money, you build more.. etc... The game has the following things to manage:
When you start out, you have a small allocation of all the above. Upgrading your main building increases your employees. Employees are required for new builds as well as power. As you go up levels and money, you can build bigger buildings and purchase land extensions. To gain experience for moving up levels, you collect money, build buildings, repair buildings, etc..
It seems like this would be a kin to the old "Theme" games like Theme Park and Theme Hospital, but it's not. In those games, walkway paths and such needed to be adjust to provide the optimal entry and exit paths. You also had to build things in ways to make the customers happy. In Paradise Island, there is none of that. It's just build, wait, collect money.
It also introduces another monetary type unit which you can pay real money to get more of.. They have some short cuts to collect money instead of clicking on each building, but this takes away from this 'other credit' which it doesn't explicitly say if you aren't familiar with the game.
If you like those types of Facebook games, you'll like Paradise Island. If you are looking for a Theme Park clone, you will not enjoy Paradise Island.