Battlefleet Gothic: Leviathan by Grand Cauldron
Blood Angels Imperium vs Tyranids Campaign but skirmish also available with Imperium vs Imperium.
Various classes and sub classes of ships available. Control battle groups of them.
Turn based but free space - no hexes or tiles. Set Power (I.e. Move) and Heading (I.e. Turn) to get Firing Arcs on enemy.
Combat is a matter of selecting Weapons that are in the appropriate Arcs to target the enemy and then rolling 'dice' to hit and damage. Weapons range from Lances, Batteries, Torpedoes, Attack Craft, Boarding Craft, and some of the more unique Nova / Hell Cannons, etc.
I believe PC has its own BFG game that's similar but not exactly the same.
Edited by Kilofix, 07 July 2016 - 11:57 AM.