Geomon

Geomon is a Mon game released for iOS devices on October 1st, 2010. The game was available until April 17, 2013, when its servers were taken down, rendering the game inaccessible.

Its background was that the scientists have recently discovered a world parallel to our own, inhabited by spirit-like creatures. EsperCorp is spearheading research to unlock the secrets of the spirit world. The player is a field agent for EsperCorp, and encounters Espers all over the world, as Geomon unlocks a portal into the Esper world right on your iPhone. Thus, you capture wild spirits to add to your collection through using a mobile device's GPS location tool and your location. The latter is important because Espers that appear change depending on where, and when, you are in the real world. A difference of 5 hours, 5 miles, 5 degrees, or 5 levels can drastically change the Espers you encounter. Even the weather attracts strange new creatures that no one has seen before! Battle and train your team to gain powerful new abilities. You can even trade with other agents to complete your collection.