Sailfish OS
Sailfish OS is a Linux mobile operating system developed and licensed by the Finnish company Jolla, descended through the Mer core from MeeGo and therefore from Nokia’s Maemo, and it still ships on Jolla’s own phones and on licensed Sony Xperia hardware.
What Sailfish OS is, in plain terms
Sailfish OS is a complete operating system and not a skin, a launcher or a ROM built on someone else’s platform. Underneath it is an ordinary Linux userland: a Linux kernel, systemd, RPM packaging, glibc and the usual set of open source middleware, with a Qt and QML application stack on top. The user interface layer, called Silica, and a handful of components such as the Android compatibility container and the Jolla Store client are proprietary and belong to Jolla. Everything else is open source, which is why the same core can be rebuilt by people outside the company.
That split matters for anyone judging Sailfish against the platform they already use. An application written for Sailfish is a native Linux application with a QML front end. It is compiled, packaged as an RPM and installed by a package manager, and it runs directly on the device rather than inside a managed runtime. A phone running Sailfish gives you a real shell, a real package database and root access if you enable developer mode.
How Sailfish OS descends from Maemo and MeeGo
Sailfish OS descends from Maemo and MeeGo through a chain that is short enough to trace in four steps. Maemo was Nokia’s Debian-based Linux for the 770, N800, N810 and N900, and it ended as a Nokia product line. In February 2010, at Mobile World Congress, Nokia and Intel announced that Maemo and Intel’s Moblin would merge into a single platform called MeeGo. Nokia’s February 2011 strategy change moved its smartphone effort to Windows Phone, and by September 2011 the MeeGo effort at the Linux Foundation had been superseded by Tizen. Only one Nokia phone ever shipped on that branch, the N9 of October 2011, which ran the release Nokia labelled MeeGo 1.2 Harmattan and which was in practice the Maemo 6 codebase.
What survived was the core. A community project called Mer picked up the MeeGo core, stripped it of the parts that were tied to defunct governance, and kept it buildable. Nemo Mobile supplied a community user interface on top of that core. Jolla took the Mer core, wrote its own interface rather than adopting Nemo’s, and shipped the result as Sailfish OS. The Mer core was later folded directly into the Sailfish OS core that Jolla maintains. The full account of that merger and its collapse sits on the page for MeeGo, and the Nokia hardware that carried the earlier platform is listed in The devices, in order.
The lineage is genuine but it is not a straight inheritance of code from every layer. Sailfish shares the MeeGo core’s ancestry and much of its middleware; the Silica interface is Jolla’s own work and owes nothing to Harmattan’s Swipe UI beyond the idea that a phone does not need a back button.
Who builds Sailfish OS
Sailfish OS is built by Jolla, a company founded in Helsinki in 2011 by staff who left Nokia when the MeeGo programme was wound down, among them Sami Pienimaki, Marc Dillon and Antti Saarnio. The name is the Finnish word for a small sailing dinghy. Jolla positioned itself from the start as both a phone maker and a licensor, selling its own hardware while offering the operating system to other vendors, and the licensing side has outlasted the hardware side in commercial importance. Jolla’s own history, including its 2015 restructuring and its later separation from its Russian shareholder, is covered on the page for Jolla.
The company’s first device, described in full in The first Jolla Phone, shipped from 27 November 2013 with a 4.5in 540×960 display, a dual-core Snapdragon 400, 1GB of RAM and 16GB of storage. It was modest hardware carrying an ambitious system, and it established the pattern Jolla still follows: a small run of its own devices alongside licensed builds for hardware made by someone else.
What makes the Sailfish interface distinct
The Sailfish interface is distinct because it is driven by edge gestures instead of buttons. There is no back button, hardware or on-screen. A swipe from the left or right edge dismisses the current view and returns to the previous one. A swipe from the top closes the application or opens a menu, depending on where the gesture starts. Pulling downward on a page reveals a pull-down menu whose options are selected by continuing the same drag, so a two-step action becomes one continuous movement.
Three consequences follow from that design. Applications remain visible as live tiles on the home screen rather than as static icons, so a running media player shows its transport controls in the grid. The whole system is usable one-handed, because every gesture starts at an edge the thumb already reaches. And the ambience system ties the colour of the entire interface to the wallpaper, which is cosmetic but consistent. None of this requires a stylus or a physical keyboard, which is the visible break from the Maemo devices that came before.
Which devices run Sailfish OS
The devices that run Sailfish OS divide into three groups with very different levels of support. Jolla’s own phones, from the 2013 Jolla Phone through the community-run Jolla C of 2016 to the Jolla C2 Community Phone announced in 2024, ship with the system installed. Licensed Sony Xperia models, starting with the Xperia X in October 2017 and running through the XA2 family and successive Xperia 10 generations, are flashed by the owner under Jolla’s Sailfish X programme. Community ports built with Jolla’s hardware adaptation kit cover a long tail of other handsets, including the Fairphone 2 and various Xiaomi and OnePlus models, and they carry no vendor support of any kind.
The distinction is worth holding on to. On a Jolla device and on a licensed Xperia, system updates arrive over the air from Jolla and the proprietary components are covered by the licence. On a community port, updates arrive when a volunteer produces them, the camera or the modem may be partly broken, and the Android layer is generally absent because it cannot legally be redistributed.
How Android applications run on Sailfish OS
Android applications run on Sailfish OS inside a compatibility container, not an emulator. The Android runtime executes on the same Linux kernel and the same ARM processor as the rest of the system, so there is no instruction translation and no significant speed penalty. The first implementation, on the 2013 Jolla Phone, was Alien Dalvik licensed from the Myriad Group and presented an Android 4.1 environment. Jolla later replaced it with its own container, which it also sells to other companies as a standalone product.
The limitation people actually hit is not performance. Google Play services are absent by design, because Jolla has no licence to ship them, so applications that depend on Google’s push messaging, its maps libraries or its device attestation checks either degrade or refuse to start. Banking applications are the common casualty. Applications that do not touch those services generally work.
How Sailfish OS is obtained
Sailfish OS is obtained from Jolla and, for most supported hardware, it is not a free download. On Jolla’s own devices it arrives preinstalled. On the supported Sony Xperia models it is bought as a licence and flashed over the factory Android image, which requires unlocking the bootloader through Sony’s Open Devices programme first. There is no ISO, because this is not a desktop operating system and there is nothing to burn to disc. The development SDK, which includes a desktop emulator, is free to download, and community ports are free but unsupported.
This site is an independent reference. It is not Nokia, not Jolla, not maemo.org and not the original Maemo Freak blog. It hosts no firmware, no ROMs and no repackaged applications, and it links to none.