Before working on games like SkyDrift, Sine Mora, and Black Knight Sword, Digital Reality was best known for their excellent 4X titles. Arguably the best of their space empire strategy games, Imperium Galactica II, is now available on iPad for $3.99.
If you've only played the two Master of Orion games (let's forget a third one exists) or Galactic Civilizations II, Imperium Galactica II is a bit like those games, but with a larger role for planetary construction and combat. From what I recall, ground combat wasn't great, yet still far more enjoyable than the obligatory boredom of the ground battles Empire at War threw at you. It seems like a perfect game to play on a tablet, so here's a chance to play it again after 12 years.