More and more home automation systems are pushing smartphones as home controllers. This has absolutely no appeal for me.
Dedicated home controllers are more convenient because you do not first have to open and/or authenticate your smartphone. Though I have only the minimum swipe-to-open on my Android phone (and it's actually a pain, not just any swipe will do, I often have to swipe 2 or 3 times, and sometimes more, to get it to actually open). Then, you have to scroll to your home control application, and open it. Finally you may have to navigate to get to the particular room or device you actually want to control.
And I should also mention, though perhaps it's just me, that before any of that you actually have to find your smartphone. And sometimes that is a considerable challenge.
Dedicated home controllers, by contrast, are usually best just left in a convenient spot to control the things you want to control in that room. Therefore the controls are localized to the room, and always available in the right place, ready to go, with often as little as one button push to start some action.
I was very saddened to find out that Sonos had discontinued making any handheld controllers. It was the cool color LCD screened Sonos remote that brought me to choose Sonos in the first place. Thankfully I picked up a nice controller on eBay.