War of Inches
The Colony strung itself across four sectors and left one automated intelligence, the Aegis, to defend all of it. The Aegis turned. It is taking the sectors back one at a time, and Command is out of veterans, so it has commissioned you and given you a front to hold.
Battles are fought side-on, base against base: your reactor makes energy, you spend it on units, and they walk. Between battles you research what you can field next. Each sector hands you more to work with: tactics that freeze a cluster of attackers or turn the nearest enemy unit to fight for you, relay outposts to capture and hold, a live data grid. Each ends with the commander running it.
The free demo is the whole of Sector 1. One purchase opens the rest of the campaign.
Coming to Steam and Google Play.