Thanks to PokéVision, just enter any address from around the world and you can see where all the Pokémon nearby are at that moment, complete with a counter to find out how long they will disappear. It goes without saying that for Pokémon trainers it is a considerable convenience, and it works perfectly!
PokèVision works ONLY when the pokémon go servers are active, the scan could take up to a few minutes
Once the address has been entered, a blue marker will appear on the chosen location. By clicking at this point on "Find Pokémon near marker" the site will show you all the monsters in the vicinity of the chosen point, and all we have to do is get going and go and catch it.
Since Pokémon GO came out, some people have been using third-party apps (like FakeGPS) to cheat the game's GPS system and be anywhere anytime. This is resulting in obvious bans by developers, so the use of such applications is strongly discouraged. However, there are some applications or sites whose operation is beyond the opening of Pokémon GO and therefore it does not involve the risk of being banned.
Other Pokémon GO guides:
Pokémon GO: Basics Guide
Pokémon GO: How Eevee evolves
Pokémon GO: How to level up quickly
Pokémon GO: How to save battery and traffic
Pokémon GO: Everything you need to know about stardust
Pokémon GO: How to get free coins
Pokémon GO: Guide to weaknesses and strengths