Last week, Jolla finally got its first batch of MeeGo-powered devices into consumers' hands.
After two years in the making, the phone was handed out to 450 people who had pre-ordered it at an event in the Finnish capital of Helsinki.
Before the week was out, I also had a brief chance to get hands on with the handset – journalists were given a couple of hours before the Jolla device was whisked back off to Finland.
First off, the hardware: specs include a lower mid-range 4.5-inch display; eight-megapixel rear-facing camera and two megapixel front-facing equivalent; 1GB of RAM; 16GB of onboard memory and a Qualcomm 1.4Ghz chip.
On the left-hand side, there's a power button and the volume rocker. On the right hand side, not a thing.
The most obviously eye-catching element of the outer design is the two-tone casing, thanks to Jolla's the Other Half.
The Other Half is an interchangeable backplate, which can be snapped on and off at will. There are currently 12 different coloured Other Half types in the wild at the moment, so while the front piece of the phone will always be standard issue black, the back can be changed from orange to pink to turquoise.
Here, you can see a white Other Half.
But the Other Half is more than just a modern update to the Nokia-style fascias of yore: they can also bring new functionality, content or settings to the device.
Once the Other Half is snapped on, it can update the phone over NFC. On the tester phone I used, it added a new look and feel called Snow White (pictured above) to the device.
Jolla is hoping third parties will run with the idea, particularly marketing agencies and content producers, and make their own Other Half backplate. A music company could, for example, sell an Other Half with a group's new album on and interviews with the band, or a football team could sell one in team colours with their latest mobile app included.
There are also hardware possibilities: Other Halves could be made with hard keyboards or extra batteries onboard.
Taking off the other half gives you a peek at the battery, which is 2100mAh and removeable. Jolla estimates it gives nine or ten hours of talk time.
The camera is distinctly average, and struggles in low light.
However, no-one's going to buy a Jolla for its uninspiring camera — the device's chief appeal is likely to be its operating system, Sailfish, which was developed by Jolla using the MeeGo OS abandoned by Nokia in 2011.
There are a couple of major differences between Sailfish and most other well-known smartphones OSes. There are very few taps required in Sailfish, for one, which has both its benefits and drawbacks.
In the lock screen, for example, there are icons in the top left hand side displaying notifications like missed calls or emails received. However, none of them are clickable – if you want to find out who sent you that missed calls, you'll have to thumb your way to another screen.
There's also no back button either, which can be frustrating when you've accidentally exited an app or webpage you were working on. While in most cases your last-used or most-popular app will be brought to the front of the homescreen (above), due to the beta nature of the OS, you can sometimes find yourself several unintuitive swipes away from where you left off.
Exiting an app when you didn't mean to is easier than you might think, given the other major difference between Sailfish and other OSes: its vertical nature.
Rather than scrolling left to, say, move from the homescreen to an app, with Sailfish, it's a case of moving downwards.
The UI will also show you when there's an action to be taken on the screen via the glow at the top of the screen (the green light at the top of the display, above).
And, like BlackBerry 10, Sailfish has a 'peek' option – by swiping up from the bottom of the screen, you can check whether any social media updates, text messages and the like have come in recently, without exiting the app you're working on. Once you lift your thumb, the peek box disappears.
Learning the Sailfish gestures is a pain initially, but after a little while with the device, it becomes a surprisingly pleasant way to navigate.
Here's the app deck that Jolla users will see, which is fairly easy to rearrange manually.
Android apps are compatible with Sailfish, and Russian operator Yandex's Android app store will come preloaded on the device. Not everything worked flawlessly when I tried it, however: one of the driving game apps loaded on the device refused to function, for example.
There's also a native Jolla app store but, as you'd expect from a youthful ecosystem, it's not overly burdened with choice — there are just tens available, mainly essentials like a document reader, many from Jolla itself.
As you'd also expect from a youthful ecosystem, there's a few bugs — a brief attempt to get an Evernote client to work met with failure, for example, and the comments associated with apps are mainly listing problems them. Jolla has promised frequent updates to the OS, and the dedicated nature of native Jolla app builders does hopefully bode well for problems being ironed out quickly.
As I was testing the device without a SIM card, I've no indication of call quality. Listening to some music was decent enough though.
Nokia's Here maps are also onboard, and look lovely on the device...
...Except when it does things like this.
Given the limited (mobile connectivity free) time I spent with the Jolla device, it's hard to give a well-balanced view of the operating system.
While there are elements that appeal, like the pulley menu plus 'peek' combination, the OS as a whole feels unfinished, and very much deserving of the beta tag. At €399, it also packs quite a high price tag for some decidedly middling specs.
However, both can be explained by the nature of the device - it's the product of two years' work by a small, interesting startup, which is fully cognisant of the bugs in the OS and the work that must be done to fix them. As a first effort, it's got a lot of potential and some interesting ideas under the hood, if it can persuade users to spend their time re-learning how to use a mobile OS.
As an open source company, it's already building a fan base of developers and early adopters — exactly the sort of people happy to overlook bugs and embrace new UIs. But if Sailfish wants to go beyond that, it needs a serious spit and polish to make it accessible, and appealing, for the everyday user.
Jolla has always talked about how it plans to license the Sailfish OS out, though it hasn't signed any deals yet. As a lure for potential licensees, I'm not sure the first Jolla device is sophisticated enough, but it shows what a bunch of clever engineers can do with relatively little money (the company has spent €20m so far) and a lot of ambition.
For Jolla to become a serious contender, it needs an equally serious partner — a company heavyweight enough to give Jolla the time it needs to beef up its ecosystem and iron out the annoying quirks, and the higher-end hardware it's crying out for.