The biggest thing that Pokemon GO players want to know is where to find the Pokemon they don't already have. The crux of the game is catching 'em all, so tracking down elusive pocket monsters is generally task number one any time someone fires up Nintendo and Niantic's smash hit.
A number of unofficial companion apps have popped up in the wake of Pokemon GO's release to serve as aids to locate specific Pokemon. We've covered a number of them here on 148apps, and while some of them are very promising, most share one common trait: They rely on players to provide the Pokemon location data to help you find the Pokemon you seek.
That means they'll always only ever be as good as the number of people who use them. What would really be helpful is if there was an app that could use the data from the game itself to guide you.
As it turns out, there's both good news and bad news on that front. The good news is that there is a service calledPokéVision that does exactly what we've just discussed. Accessible at www.pokevision.com, it uses Niantic's own API to find where different types of Pokemon will spawn. Even better, it can even determine how long they will be in a certain location -- and anecdotally, this writer has found that to bePokéVision's killer feature, as two teenagers using the site were able to tell me exactly where a rare Pokemon was located in our town and how long it would be until it despawned.
The only caveat for this magic is that it isn't able to give any information on Pokemon summoned to a specific area using Incense or Lure Modules, since those monsters are outside of the game's normal processes. Considering how common it is to see a Lure Module in use almost anywhere you go at the current time, that's not insignificant. Perhaps obviously, the Pokemon GO servers also need to be up and operational. If not, thePokéVision scans can be slow or even completely inaccessible.
But we promised some bad news as well, and here it is: There is noPokéVision mobile app. Why not? The FAQ page doesn't provide any insight, but the educated guess would be the way it uses Niantic's data would be something the developer could get kicked out of the App Store. Or perhaps thePokéVision team simply wanted to perfect its technique without worrying about coding an app too, but the first theory seems more likely.
For now, you'll just have to content yourself with using PokéVision via a mobile web browser when you're out on the hunt. It's not all that terribly inconvenient, and considering how big a help it is, it's something you'll want to check out for yourself if you're a dedicated Pokemon GO player.