Angry Birds Casual, Rovio's back-to-basics puzzler, has quietly soft launched for iOS. It aims to offer an easy-to-learn experience that strips away some of the complexity of the more recent entries in the incredibly popular Angry Birds series.

If you've been living under a rock for the last decade or so, Angry Birds is a physics-based puzzler that sees you flinging birds towards dastardly pigs and precarious structures in order to boost your score and beat the level. The challenge stems from only having a limited number of birds to use, meaning you're going to have to be efficient and accurate.

Angry Birds Casual sees the "most endearing Angry Birds characters yet" venture out on an epic quest to unite fireflies with their soulmates. How cute.

There are currently hundreds of levels to play through spread across a number of distinct worlds. As you progress, you'll earn coins to exchange for boastworthy rewards.

PocketGamer.biz has confirmed that the test will run for roughly one to two months, and those in the US, Finland, Poland, and Sweden can get involved if they so desire. A global release date is yet to be confirmed, but hopefully it's not too far off.

A few weeks back, Angry Birds Tennis soft launched in the US. That one's an arcade tennis game featuring a host of fan-favourite characters. I didn't get a chance to play it, sadly, but a global launch must be on the horizon.

You'll find Angry Birds Casual available for download now as a free-to-play title from over on the App Store. Curious Android players should probably expect it to hit Google Play at a later date. 

On the hunt for more top-tier puzzlers? Well, you're in luck! Here are 25 of the very best on iPhone and iPad