The iOS version of XCOM: Enemy Unknown represents something of a gamble. Developer 2K China has spent time and money of porting last year’s console and PC strategy favourite to iPad and iPhone. This is no companion app – XCOM iOS is the real deal. Apart from some derezzed visuals and a slightly smaller map count, what you’re looking at is the complete XCOM experience in portable, touchscreen form.

If you were abducted by aliens and missed the hype surrounding the game original release, here are the Cliff notes. You are the commander of XCOM, a science-powered military organisation charged with protecting the future of mankind by detecting and eliminating alien threats.

Gameplay is split into two distinct categories. For half the game you’ll be engaging in top-down turn-based combat, using a small squad of specially trained XCOM troops to investigate and neutralise extraterrestrial activity. Your objectives range from shooting anything that isn’t human, to research gathering and search and rescue missions.

The rest of your time will be spent back at your base. Here, you must divide your focus among a number of important responsibilities. Troops must be recruited and trained via the barracks. Your science team is on hand to research alien tech, and use the info to create more advanced armour and weaponry. Building all this fancy gear requires an engineering staff, whom you must also manage and expand accordingly. As XCOM is a global initiative, you need to ensure your allies around the world remain calm during the invasion, and approve of your efforts. If they lose faith in you, you lose valuable funding and resources. All of these elements must be balanced to keep the XCOM initiative alive.

As with console and PC versions, what makes XCOM great is its deliberate and unforgiving strategy mechanics. It’s essential to invest thought and consideration into each and every move you make. Caution is the keyword here. While you can dash a soldier headfirst into enemy territory and attempt to wipe out the alien scourge long gunman-style, this will inevitably result in the death of your unit. And when we say dead, we mean dead. Soldiers killed on the battlefield cannot be resurrected. Instead, you must gradually train up another rookie to take your fallen comrade’s place.

To survive you must advance carefully, taking advantage of available cover at all times. Managing your troops perks and items is important, too. Knowing who has the ability to dash and shoot in a single turn, could prove the difference between success and failure.

However, battlefield prowess is useless if you can manage your base properly. Choosing the wrong project to fund, or ignoring a particular country’s security can cost you valuable equipment and cash, and even the game. If you don’t wish to restart your efforts from scratch, you’ll want to choose carefully, and save regularly.

It goes without saying XCOM’s visuals have taken a hit on its journey to the App Store. Textures are more basic, and battlefield are lacking some of the fancier lighting and atmospheric effects. The touchscreen controls gel pretty well with the strategic point-and-click action. We noticed that the game had trouble differentiating between some of the gesture commands, and occasionally we’d end up moving the camera when we meant to move a soldier. However, none of these niggles interfered with our enjoyment of what is a top-tier port of a first class game.