Public market investors won't have the chance to invest in these pure-play mobile app companies for a while, so let's think of some companies that are public which should be able to remake themselves as a mobile-only type of app.
Yelp(YELP) : Yelp saw a big jump in its stock on Monday afternoon after everyone digested the Facebook-Instagram news. Perhaps more than any other recent IPO, Yelp is perfectly situated for this big secular shift from PC desktops to mobile. As Steve Jobs said a couple of years ago, people don't "Google" on their mobile devices, they use Yelp. They are seeking to get instant information customized to their mobile device. Yelp offers that information much better than Google.
LinkedIn (LNKD) : Even though LinkedIn doesn't make money in mobile, its service becomes much more popular as the use of mobile proliferates. They make money from ads and from helping companies find people. The more their users like the site, the more attractive the service becomes for companies trying to hire them. More LinkedIn users are accessing the service from their mobile devices throughout the day. CEO Jeff Weiner confirmed this during the last earnings call. Unlike Facebook, LinkedIn doesn't lose money every time one of its users accesses its site from a mobile device.
What about Groupon(GRPN) ?
This is still up in the air. Groupon's mobile play is certainly going to be Groupon Now. However, that has yet to really be rolled out. At the moment, Groupon is still a Web-based sign-up service. Mobile shouldn't hurt them as much as it hurts Facebook, because Groupon isn't an ad-dependent model.
Facebook does face a major challenge with the shift to mobile. They are taking out a mobile-only competitor by acquiring Instagram but this doesn't help Facebook make money from mobile. They still need to determine how to do it. Stuffing ads into people's news feeds is probably not the right answer.
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