This is a bit of a bait and switch, because all of the options the author lists are solving problems (even if just improving upon existing solutions, you are still solving sub-problems of existing solutions). Instagram readily solved a problem: photo editing / stylizing had been difficult and/or expensive prior (yes, I hate their filters as much as the next guy, but most people find some value in it). It may have not been the first app to do it, but it still solved a problem.