Battle Academy - WWII themed TBS with some light wargame elements.
Breach and Clear - Similar to XCom (cover system is a complete copy) but both sides turns take place at the same time. Military/swat themed.
Door Kickers - This one isn't turn based, real time with the option to pause and give orders at any time. Swat themed.
Unity of Command - This is more a beginner level wargame that's turnbased, WWII eastern front.
Battle of the Bulge - Another WWII themed beginner level wargame that's turnbased. This ones probably even easier to get into than UoC.