They don't need you to "check-in" when they are grabbing your location every 15 minutes in the background. They've also built APIs into ad networks that ping their location database with coordinates millions of times a day to find relevant ads. There's thousands of apps using ad networks that funnel location data back to 4sq.
Techies may have abandoned them, but they still have a ton of middle America thinking that 4sq is cool. My mom for example.
On another note, 3-4 years ago I had access to a large anonymized bank/credit card transaction database from a well known company. It had about 1-2% of all transactions in the US by our estimates. When we modeled the quarterly sales of Walmart compared to it we found that it was incredibly accurate going back 5 years, even with 1/50th of the US population.
Another similar company who is making a ton of money off data on the backend is Shazam.
If I recall correctly a few years back they were doing $100m a year by basically being able to give everyone in the music industry insight into what's the most popular and upcoming songs in every major city.
However, with the popularity of Spotify I'm guessing they're losing a lot of market share in the mass music metrics space.
> "The SEC sued colleagues Nan Huang and Bonan Huang in January 2015 alleging they made hundreds, if not thousands, of keyword searches on their company's private database for sales data on at least 170 publicly traded companies from November 2013 to January 2015."
Ref: http://www.reuters.com/article/us-sec-capital-one-fin-inside...
It seems like the biggest problem was misusing non-public Capital One data. Imagine if a personal finance app made that part of their business model and got scale.
Something like Mint could front a powerful consumer investment strategy..
I used to work for an Australian consultancy "Quantium" who are doing exactly this and scale transaction data using national statistics data [1] - page 13
[1] http://blog.abs.gov.au/Blog/natstats.NSF/dx/Wade%20Tubman.pd...
If they are tracking users who are not actively using the app then that is just plain creepy and wrong. Are you saying Foursquare tracks background location to thus day for users who installed it and tried it out once a few years ago? That would explain the database value but it's Creep City.
Operating systems should expire those background privileges for apps that fall into disuse (or do they already?)
Even if both of their apps fail, they likely have a lot more inbound data from these large partner sources to continue to build out a pretty healthy pipeline to provide better data.