Nothing like actual puzzles or (obviously) roadblocks, no. Basically by moving with the app you can scan your surroundings and, using a limited resource, plant flowers on your path. Along the way you level up seedlings and eventually pluck out new pikmins to accompany you, and you discover stuff around you (fruit, big sprouts).
You can then send your pikmins in expeditions to retrieve fruits. If you notice them after the fact, it means your Pikmin may have to travel from where you are now to get those, and come back to you. You can follow them on the map, It gets a bit crazy when you’ve traveled a few hundred kilometers in between. The type of Pikmin will help, colour compatible-ones will work faster, purple Pikmin are strong like a bunch of normal ones, pink are very fast if they’re the only type (since they can fly) etc.
The collaborative part is mostly around big sprouts (corresponding to landmarks like in other Niantic games, so real life monuments, parks, curiosities etc). You’re supposed to plant a lot of flowers in a radius around them to make the plant bloom and then everyone can send an expedition to the giant flower to get a bunch of resources.
It doesn’t have a lot of depth really, but it makes for fun interactions. Your Pikmin all come with their place of origin, and get decorations depending on stuff around that place (seashells on beaches, acorns and beetles in forests, lots of random junk for specific buildings, like stores, train stations, parks, restaurants,…), and the app also incorporates pictures you may have taken in those places to make a diary of sort.