The North American iTunes store is chock full of amateur Pocket Monster catalogs, assembling data from the popular Nintendo creature collecting series. They might soon be obsolete, should the official Pokedex for iOS released today in Japan make its way stateside.
From what I can gather from the app's official page, the iOS Pokedex is quite similar to Pokedex 3D Pro for the 3DS. Fans can search through the entire Pocket Monster catalog, sorting by number, type, and other sorts of statistics you sort Pokemon by. The critters themselves are rendered in 3D, able to be rotated and posed in various ways. Or they can just wander about the screen in real time. Either way, tons of Pokemon, at your fingertips.
The app starts at 170 Yen (around $2) and includes Pokemon numbered 494-647. Three additional sets are available for in-game purchase at 500 Yen ($6) apiece. That's $20 for a full Pokedex.
I contacted the North American branch of The Pokemon Company to see if there were plans to bring the app stateside, and was told there were no announcements to be made regarding a North American release at this time.
But you know they're going to. They have to. We have to catch them all.