It's been given away in countless Humble Bundles, plays excellently on mobiles and probably echoes the vibe of Counter-Strike in a turn-based format better than some of those browser games out there.
Mode7 Games hasn't been talking about Frozen Synapse for a while though, having spent the last couple of years focusing on Frozen Cortex. But the more tactical shooter is getting a sequel, and it's due out this year.
I've contacted the developers for further information, but for now the only tidbit available is a line on the site that says "Open World Tactics".
There's also a release date of 2016 and one of the developers posted on Twitter that "most of the 50 things" that make the sequel interesting haven't been announced yet.
Mode7 will be showing off the game at GDC next month, so expect to hear more about the top-down simultaneous wall-destroying simulator then.