The Nest feed for PoGO++ is DONOR only.
https://nest.pokego2.com will list all pokemon clusters in our pokemon feed for PoGO++.
You can use this feed to detect coordinates where a lot of pokemon are grouped together based on your given filter. The output of this feed will give the center of each cluster as coordinates, will show how many pokemon are in the cluster and will show which pokemon appears most inside that cluster according to your given filter.
You can use all possible filters of the pokemon feed (see the pokemon feed docs for all options).
This feed will group all pokemon based on their coordinates together. By default it will round all coordinates to 2 digits, but you can change this by adding the additional digits filter, for example: /digits-3 will round all coordinates to 3 digits for the grouping.