If you're not sorted for Christmas by now, then shame on you. Have you seen the date? It's the 21st! Stop reading silly little articles on the internet and go and get shopping!

We jest, of course. We appreciate every single member of our readership - including you, if you can believe it! - and are rewarding you all this Christmas with our very own Advent Calendar.

From December first, right up until Christmas Day itself, we're giving away codes of the very best premium games which launched on mobile this year to members of our community, the App Army.

For more information, check out the post from December first. But if you know the drill right now, read on to learn why you're a doofus for not playing Invisible Inc..

Sounds like some kind of detective agency

Solid assumption. Invisible Inc. challenges you to take over a team of stealthy agents as you infiltrate the most dangerous corporations in the world over the course of a bunch of missions.

You select a character from a pool of 10 at the beginning, then customise them, adding useful programs, items, and augments to their arsenal to help them overcome the many obstacles in their way.

It's difficult to plan ahead when the levels are randomly generated each time - but that does keep you on your toes, and leads to some exciting scenarios that you'll be desperate to discuss over the water cooler at work the next day.

We absolutely loved Invisible Inc. at review, giving it a Gold Award and saying: "Klei's hybrid of cyberpunk sneaking and turn-based tactics is a must-play for fans of the stealth genre".

I want to be an agent

If you'd like to have a stab at being an agent yourself but don't really fancy paying for it, simply join the App Army here, then write your name as it appears on Facebook in the comments beneath this post.

We'll then select the lucky winners and distribute the codes within one working day as a PM on Facebook.

We only have iOS codes for this one mind, so if you're Android only you'll sadly have to skip this one. We do have plenty more for you in store though, so check back another day!

What's the App Army? The App Army is Pocket Gamer's very own community of mobile game experts. Each week, we provide them with a bunch of free codes and early access to the hottest upcoming games so they can provide their thoughts in features like this. We also host regular community-driven events with them in mind like tournaments, giveaways, and multiplayer evenings. To join, simply follow this link to the page on Facebook and request access. We'll get you in right away!