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Didn't work out for Organic Maps. Merely allowing to access map data makes you un-family-friendly. Or at least that's what we can assume, since Google won't indulge in specifics. https://news.ycombinator.com/item?id=41272925

Even Tapatalk had to filter out "adult" forums - and it's just a client to connect to 3rd party forums.

On Twitter you can find actual porn straight up.

There are some protections for hosting illegal data (real illegal, not EULA-disapproved), but they tend to go away if the host does any kind of editorializing (like showing the data through an algorithmic feed).

Google Search is different yet, since they aren't the primary host.