Only log me, but don't let my friends know: You know your privacy is respected jack shit when the least intrusive setting is letting the service know and log you, but not letting your friends know.
The real question isn't that what it sets by default, the question is why that chat app needs to know and log your location in the first place? Why does it not only get it and send it when you choose to share? What kind of enhancement does it give to your fucking """experience""" when it logs your location like that?
@cassowary, geotagging your photos can be done without logging your location on the server. It can be done locally. Plus, I thought that Snapchat does not keep the pictures you've taken? (I have been out of that since then, so I don't know.)
I'm not by any means a Snapchat power user. But I really like the way my phone tells me where my normal photos are taken — it makes it very easy to find the photos. Also, any chat app would benefit because it's very easy for me to remember "i was talking about foo with Bar when I was over in Baz", but much harder for me to remember when that happened. So to me location tracking would offer many useful features. (They may not be worth it, and even the useful ones might not be available, but those aren't answers to the question you asked.)
In Snapchat your location is used for the geofilters, I guess that's why they have to get your location. I do think they should have an option to turn off geofilters and not use your location at all though.
If you use the map it asks you if you want to turn it on, most people click through it looks like. Now someone write a PoC to keep a log of where everyone goes.
This was back in spring-summer 2015.