Rovio has been an interesting company to watch. In the space of a few years it has gone from being an unassuming Finnish studio on the edge of bankruptcy to the custodians of one of gaming's most famous franchises.
Now the world is watching with bated breath to see exactly how Rovio plans to follow up its billion-download hit.
Bad Piggies is the latest, tentative, rather reserved step towards a true follow-up. It's yet another physics-puzzler, still set in the world of Angry Birds, but with the pigs as heroes rather than villains.
It's certainly something new. In each level you're given a toolbox of building blocks - like crates, wheels, desk fans, helium-filled balloons, and motors - and you've got to assemble a vehicle that will ferry your pig to the finish line.
When pigs fly...
You hit 'play' and gravity takes over. Wheels roll, balloons lift off the ground, and unbalanced vehicular monstrosities fall flat on their faces. Depending on the tools available, you'll also be given any number of buttons so you can turn on fans or detonate boxes of TNT at will.
It doesn't quite have the simple, kinetic thrill of Angry Birds, but there's something quite attractive about seeing your home-made creation trundle down a hill - especially when it's some wobbling great jalopy with a wheel on its roof and a spring on its bumper.
And especially when it cartwheels into a spectacular crash and ejects your pig passenger through the windscreen.
It's playful and creative, even inside the quite restrictive boundaries of each level. You get to try out ridiculous ideas, and flash an ear-to-ear grin when your madcap plans actually work. Bad Piggies is a bit like the best physics lesson you had school, but on every day of the year and with no theory in between.
It's also more predictable, and far less finicky, than Rovio's previous puzzlers. In Bad Piggies you have to place your tools within a strict grid - which is in stark contrast to Amazing Alex, where you could shift toys by tiny amounts, for dramatically different results.
There's a lot of content on offer, with about 100 levels available from launch. But that's not the end of it. Each stage has three goals which all require very different vehicles and strategies. You might want to build a land speeder that's tuned for the timed goal, or a dependable buggy to get over the line without breaking into bits.
There are goals for collecting crates, and ones for making a vehicle that doesn't use the most obvious tool in your collection. This system gives you good reason to replay certain stages, and forces you to try new tactics.
It's just a shame there are no real social features, aside from Game Center achievements. It would be brilliant to show off a particularly insane contraption to a friend, but short of physically lugging your iPad to his house it's not possible.
Now, Bad Piggies is certainly good fun. It's better than Angry Birds, far better than Amazing Alex, and of the same quality - in imagination, personality, and smarts - as the wonderful Angry Birds Space. It's possibly the best game that Rovio's done yet - but the formula is starting to feel a tad stale.
With so many physics-puzzlers on the App Store, with quirky cartoon graphics and three-star scoring systems, maybe it's time for Rovio to try something new.