Roku boxes are all the rage right now, offering cheap and easy streaming of services like HBO Go, Hulu Plus, and Netflix.
Of course, another box means another remote, and Roku's clickers are so small they can easily vanish into the couch cushions, never to be seen again. (Well, unless you look.)
The app connects to your box via your home network. I quickly and easily linked my iPhone 4S to an older Roku XR--though judging from some App Store reviews, some users have had trouble with this initial setup. (Check Roku's support page if you encounter a similar problem.)
I found Roku for iOS superior to the stock remote in many ways. For one thing, it offers one-tap access to your subscribed channels, which beats the usual method of navigating to the Home screen and scrolling through the list. You can also browse the entire channel library and add/remove channels as desired. Very convenient.
As for actual menu navigation, the app relies on swiping in place of left/right and up/down buttons. This works just fine, though it does seem like a bit more work than tapping onscreen buttons would be. It would be nice if Roku let you toggle between swipe and button controls.
That said, swiping has one key advantage: you can do it while keeping your eyes on the TV. Buttons would require a lot more glancing down at your phone or tablet.
Of course, the real perk here is the app-powered keyboard, which makes searches infinitely easier than navigating the Roku's own keyboard. That alone makes the app a must-have.
Indeed, I'd say that if you own a Roku box, you should definitely have the Roku app. If nothing else, it's a spare remote. And it's free, so there's literally no downside.
One last thing: I must take this opportunity to gripe about Comcast not supporting HBO Go on Roku, even though it allows it on iOS apps. Why, Comcast, why?! OK, end of rant.