This year's Mobile World Congress seems to be the year for fledgling smartphone operating systems - we've already seen FireFox OS but now it's the turn of Finnish manufacturer Jolla. It has its own custom Sailfish OS, which is a continuation of Nokia's now defunct Meego - fitting, considering the company is comprised of former Nokia developers. It was running on the self-titled Jolla smartphone, and we've been trying it out in order to bring you some first impressions.

Sailfish OS

Sailfish in its current form is a custom-built smartphone operating system based on Linux, along with code heritage from the Meego OS last used on Nokia's N9 smartphone - arguably a handset that was ahead of its time. It is still very much a work in progress, having only recently reached version 1.0, but it has already been shown working on existing Android handsets and is now available on its own unique hardware - more on that below.

The swipe gesture-based navigation feels alien when coming from Android; there's no onscreen menu buttons or hardware keys to return to the home screen or switch between apps. If you've used Blackberry's BB10 operating system, however, you'll feel right at home. A double-tap will wake the screen, much like LG's G2 , while a swipe in from the left of the screen will send you back to the previous menu or page. Swipe from the bottom and waiting notifications are displayed. Swiping down from the top will close the currently open app and return you to the home screen, where you can pin recently opened apps for quicker access. Scrolling down reveals a number of pre-installed apps, including a web browser, phone dialler, messaging app, email client, media gallery and maps app.

Sailfish includes the Jolla app store, which currently has a selection of several hundred apps. That's a drop in the ocean compared to the Google Play Store, but because Sailfish is written using some of the same Linux code as Google's Android, you're able to install Android APK files onto the handset and use your familiar apps. We saw Angry Birds working flawlessly on a Jolla handset, albeit with visible hardware back and apps buttons which are baked into Android apps when they detect a phone without physical buttons.

The minimal interface looks gorgeous, with sensible layouts for each app, large icons and colourful thumbnails for music albums or phonebook contacts. It's almost like a combination of Windows Phone simplicity and Apple's visual impact, but with the customisation of Android.

Jolla phone

The phone itself is a fairly mid-range device; it has a 4.5in, 960x540 resolution display, dual-core Qualcomm Snapdragon 400 chipset running at 1.4GHz, 1GB of RAM, 16GB of onboard storage with microSD card supporT and an 8-megapixel rear camera. Were it running Android it would be the definition of mid-range, but it's ideally suited to test the waters for Sailfish.

Made from soft-touch plastic, the phone is comprised of two parts. The colourful rear covers can be peeled off and swapped to give the handset a fresh look. In an excellent design twist, an NFC chip built into each one will automatically adjust the Sailfish system colours and wallpaper to match.

The screen may not have a particularly high resolution panel, but the large, legible text and colourful Sailfish icons still look great on it. Viewing angles were excellent too, although only if there were no lights directly overhead - the screen is incredibly reflective, and also quickly attracts fingerprints.

Although we could only judge the rear camera based on how images looked on-screen, we were impressed with the number of manual controls and pre-sets that are available to play with. Everything is sensibly arranged too, staying out of the centre of the image to help you frame your shots until you call down the more detailed menu.

It's not clear what baseline hardware is needed to run Sailfish smoothly, but it's a fair bet that the mid-range Snapdragon 400 exceeded it; everything felt incredibly smooth, with animations flowing without any signs of stutter. The most demanding app we tried was Angry Birds, but that worked flawlessly.

Unlike almost everything else here at MWC, you can actually buy a Jolla handset today; it's available online through the Jolla shop . With shipping and handling, you should expect to pay £340. That's an awful lot to ask for a fledgling operating system running on mid-range hardware, but unless you're prepared to hack your existing Android device, or wait for Jolla to release its forthcoming Android launcher later in the year, it's currently the only way to experience Sailfish OS on a smartphone.