Jim Cramer is curious, especially since both companies lie at the very heart of new media and the migration from desktop to mobile.
"Most of the Internet companies I follow, indeed most of the technology companies I follow, have been hurt, in some cases almost annihilated, by the migration from the desktop to the handheld," Cramer explained. "Groupon and Yelp, however, have managed to harness mobile, quite well."
The popularity of their mobile apps is partly due to the significant focus both companies put on local commerce - a somewhat underserved niche in Internet.
It seems as people move about town, they like to click on the Groupon app and check their smartphones for coupons. And they like to click on the Yelp! app for restaurant and hotel reviews, as well as insights on nightlife, shopping and more.