A cell tower could be used to triangulate your position, but we're talking about an iOS app not being run by your phone company. This is why we have security features in iOS, at least in theory!
If you do not have location sharing enabled, how could a company running an app know about you? I can think of things like
- the cell phone company is selling your location info to the company, that has your phone number via SMS
- Guessing based on EXIF data from previous posts and previous location service usage ("you're probably where you always are")
Is there something else I'm missing? The point here is we are talking about an app on your phone (not some Apple service or the phone company) knowing where you are
If you do not have location sharing enabled, how could a company running an app know about you? I can think of things like
- the cell phone company is selling your location info to the company, that has your phone number via SMS
- Guessing based on EXIF data from previous posts and previous location service usage ("you're probably where you always are")
Is there something else I'm missing? The point here is we are talking about an app on your phone (not some Apple service or the phone company) knowing where you are