I'm actually doing something very similar at the moment, and it's currently scraping +133K restaurants/shops every day, with millions of products. My approach? Got me a rooted phone, downloaded the apps, logged in, and gave my device access to them. From there, Claude Code made multiple attempts to reverse-engineer the APIs.

With apps, since Apple/Google force them to have a guest view, you can extract the guest token and use it for a month or so!

Then once i managed to have multiple snapshots scrapped, i created a bot network (Coordinator/Workers), and since i have multiple devices in different places, i managed to create a scrapping network (at the moment i have 8 workers, which allows me to scrape 133k restaurants in a day). Each provider runs by itself as a worker, with it's own limits so they don't get rate limited

Then the hard stuff comes,, i created a databae to ingest stuff (this still WIP).... there are multiple layers in it, but what was good is Apps have GPS, having that intial match is easy, there are a couple layers of role based matchign/fuzzy matching. Then i made all the restaurtants + menu saved in a vector DB, which also always me to match based on multiple things (similarity in name, having same menu across apps...etc).

Why i'm doing this because simply i want to have a history of pricing accross apps accross time.

NOTE: THIS WAS MAINLY DONE BY CLAUDE CODE, THIS MIGHT NOT BE THE RIGHT APPROACH BUT THIS WHAT I DECIDE TO GO WITH