The #2 app in the App Store claims to help you find Pokemon

What can challenge "Pokémon Go" as the hottest app in the world?

Another "Pokémon" app, of course.

"Poké Radar" is a new iPhone app that claims to help you find Pokémon by taking submissions of their locations from other players. It was number two in Apple's App Store Monday morning. (There are several similar apps for Android too.)

The app is pretty straightforward. When you spot a Pokémon in your area, you can submit it in the "Poké Radar" app. In theory, other users can go to that location to hunt down the same Pokémon you just found.

However, it's not a perfect system. "Poké Radar" isn't an official app from Niantic, the company that made "Pokémon Go." And there's nothing stopping people from fibbing about the Pokémon they find. Plus, many Pokémon appearances are totally random, so just because one player found that Bulbasaur on a certain street corner doesn't mean you will too.

So, how can you reliably find the Pokémon you're looking for? Unfortunately, there's no perfect science to it. But the game does take your location's geography into account, so it's best to learn which Pokémon are attracted to rivers, parks, oceans, beaches, or whatever.