Combined with notifications and a powerful processor with online connectivity (meaning social sharing), games like Dragon City Mobile are ripe for explosive popularity.
Dragon City Mobile is one of the finer made city management games on the App Store. While not wholly different from many of its contemporaries, it is fun to play and incredibly deep in terms of content. The goal of the game is to generate resources, build habitats and buildings, and then hatch and grow dragons. Players must feed their dragons, which requires the creation of farms to grow food. Every resource in the game is limited so they must be carefully distributed, though you can gain more resources at any time by sharing with friends or simply paying for them with in-app purchases. This mechanic is purely optional, however, and the number of free features included already allow for hours of engaging gameplay.
Dragon City Mobile is a fun game that works well for both children and adults. Many will be turned off by the buy-to-expedite game mechanics of in-app purchases; but since these are purely optional, as is social integration, the game can be played solo for free and still be quite a bit of fun. If you're looking for a new city builder, this is a great one to check out.