Pokemon Go has been a huge hit worldwide. Even I got convinced into jumping in with the hype. I never played Pokemon my entire life and just started now in my 30's. Well, maybe I watched the cartoons back in high school but never really touched the gaming part.
After playing Pokemon Go for 2 weeks I have started to get a grasp on how it works, even posted a bunch of articles here like using Zubats as target practice, using the CP and IV calculators, even wrote an update about Legendary Birds and Detective Pikachu.
I also start to wonder how these wild Pokemons are spawned. I searched the internet but found no concrete explanations on why a Pokemon spawns in a mall or in a church or some big rock across the hospital. There are observations and estimates on how this works.
Pokestops, Lure Modules and Incense
First, you would notice that you frequently get more Pokemon on areas near Pokestops. Pokestops are usually landmarks in your area, provided you are already exposed at Google Maps. These landmarks are churches, historical landmarks, art murals, famous establishments, big fountains, and so on. The further you are from these Pokestop clusters, the less to none chances a wild Pokemon spawns.
There is also a 'lure' feature where players can drop at Pokestops', this increases the chances of a wild Pokemon appearing.
Incense also help attract wild Pokemon to you. My note though, I tried using Incense in a remote area, far from Pokestops, no wild Pokemon appeared which is ironic because, you know, wild Pokemon should be out 'in the wild' not in urban areas.
Usually, malls are full of Pokestops, I tried going to a newly-built mall but this one doesn't have any Pokestop yet. The explanation simply lies on the next paragraph: 'Ingress'.
Pokemon Go and Ingress
Yes, Pokemon hooks up with Ingress' database in terms of landmarks which explains the new erected mall I visited for Pokestops has not been on the list yet. Most, if not all, Ingress Portals are converted into Pokestops in Pokemon Go. If you have played Ingress, then you'll sure know how to make your way around Pokemon Go. If you haven't of Ingress, then the best natural indicator you will have are your area's landmarks. You can refer to the Ingress map database here.
Literally travel the world
Escape.com.au reported a list of Pokemon Go hotspots all over the world. Travelers now include catching wild Pokemon in Pokemon Go as part of their travel itinerary. The report lists hotspots such as the Circular Quay in Sidney to the Metropolitan Museum of Art and Central Park in New York, Big Ben, The Coliseum in Italy and all other popular world-wide tourist attractions.
Any proven formula?
As stated, there is really not enough information on the internet to create a concrete formula on how these wild Pokemon appear in Pokemon Go. However a website called Pokesnipers.com gives you data in coordinate form on where to find rare Pokemon in real-time. This is used in parallel with Pokemon Go bot cheats where you 'teleport' to far places around the world.
Just remember the basics
If you just want to catch wild Pokemon in your local area, the best places to go are old landmarks, art murals, old malls, and other significant urban areas that are at least 4 years old.