Both ads are apps that provide a easier way to improve busy people lives. The Yelp ad shows a few commercials that identify different people situations that yelp could have or should have helped people. The spoke man looks like a hipster who usually uses yelp. And it is known that hipsters use yelp anyway. Yelp’s slogan is when you need it and wherever you need it. This gives a perfect example of what they are selling to people. Yelp seems to have an younger audience.
On the other hand foursquare seem to be showing a completely different ad. They are using two different people with two different likes. The foursquare seems to be using a checklist that probably can lead you to what you want. The slogan for foursquare says “what you like and leads you to a place you’ll love. Their audience is for busy adults who are looking for quick places to eat, or other things
I find your suggestion that Yelp is going for a younger audience an interesting one but you don’t offer any evidence. Maybe the zany humor? The narrator, who you refer to as a hipster is probably 30-something so not a kid. Only the young woman with her parents who is being gifted a golf club seems particularly young though certainly there is no one my age. In the foursquare ads there is an older man paired in one ad with a younger man. I think you have a case. You just need to articulate it more clearly.