While the idea of a co-op XCOM board game sounded great, the fact it required use of an app turned a lot of people off. It turns out calling it an "app" is doing it a disservice, though.
PC Gamer got some hands-on time with the game, and what they write about the app makes it sound like a chess clock. If a chess clock could talk, and make up new rules every few minutes.
While the game's official announcement was a little vague about the app's role, in practice it's actually a fifth player of sorts, called a "Central Officer". The CO is in some ways running the game, telling each player what to do and when to do it.
Here's how it worked in practice, in my demo game:
"Commander, assign your interceptors. You have 15 seconds."
Africa's about to fall into panic. Europe's no better. I have six inbound UFOs, and six interceptors, but I'm short on cash. If I move to defend, I'll have nothing to give my ground troops, who are repelling a base-invasion at XCOM HQ. And the Science Officer won't shut up about wanting to get more salvage.
"Five seconds!" screams my Central Officer.
I let Africa fall, assigning three interceptors to Europe.
So, yeah. Tense! Unpredictable! Unless your gaming setup makes it impossible to get a laptop or iPad or whatever somewhere near the table, this sounds amazing.