Ross Rubin, writing for Engadget:
Perhaps the best examples of Samsung's love of features that embrace marginal utility are ones that require multiple Galaxy smartphones to work. Topping a Group Play feature that allows one to use four Galaxy smartphones as surround speakers (despite smartphones being infamous for poor-quality speakers), the company added Multi-View, which allows you to line up four Galaxy Notes and play a video that stretches across their displays. Creators of tiny video walls rejoice.
Perhaps there is a method to the madness; Samsung could be seeking to differentiate itself for those who embrace technology for technology's sake, who buy into the promise of the possible versus the practical. Many features that we take for granted and use today were once considered experimental, gimmicky or derivative and Samsung may just be hedging its bets. But bleeding-edge features that approach the status of demos do not line up with the enormity of the market that buys even Samsung's flagship phones (or perhaps four of them). For Android handset vendors such as Motorola and LG, and others who would like to cut into Samsung's massive market share, there may be opportunity in drilling home that their feature sets are not just fun, but also functional.
If you watch the iPhone event and look at Apple marketing copy, it's pretty easy to glean that all the talk about not including features for features sake is a not-so-subtle dig at Samsung. The thing where the Galaxy S4 can detect where your eyes are and start/stop video playback accordingly is, to me, more gimmicky than useful. Is it truly better than simply tapping to bring up the controls and hit Play/Pause? No. On the other hand, the fingerprint sensor in the iPhone 5S, I think, is truly useful.