The gameplay allows you to earn coins by employing up to three Denizens in each of your businesses, with five Denizens being allowed to live in each "Dwelling," or apartment. Each Denizen has a dream job or set of jobs that they're better at than others, with businesses being available in five basic categories (entertainment, service, food, crafting and kingdom). In addition, you can build a special Dragon layer with Gems, the game's premium currency, and you can spend Gems to upgrade your floating elevator, used to bring guests to the different floors farther and farther underground.
At ground level sits your castle, with a princess that you can name. She'll give you light quests as you play, like adding a certain number of Denizens to your dungeon, and she'll also be able to tell you which of the five business types your Dungeon needs most to keep your citizens happy. There are special Denizens that will arrive with power-ups (instantly stocking all Goods at a business, for one), and you can also upgrade your businesses (using Gems) to make them more profitable over time.
By now, the gameplay mechanics here shouldn't be new to many of you, as, again, the only major differences come in the direction you're building your tower and the ability to speak to your castle's princess for light quests every now and again. If you're simply enamored with the tower-building genre, feel free to download this one, but don't expect true innovation.
Have you tried Glu's Lil' Dungeon on your iOS device? How many tower buildings games is "too many?" Sound off in the comments.