Mer: Remastering Maemo

Mer is an outgrowth of Nokia's Maemo environment, designed to flesh out the tablet-centric operating system into a full-fledged Linux distribution suitable for embedded and desktop systems of all description. The project's genesis was an effort to back port the upcoming Maemo 5.0 release to no-longer-supported Nokia N800 and N810 tablets, but it has subsequently evolved to run on BeagleBoards, embedded navigation devices like the Pocket LOOX, and standard x86 hardware.

Nokia released the first Maemo 5.0 SDK alpha this month, building towards beta and final releases before the end of 2009. Codenamed Fremantle, 5.0 will be the first major upgrade since June of 2008. Although much online discussion has centered on speculative hardware devices that might accompany the release, the more significant changes in 5.0 are under the hood: Nokia's concerted effort to synchronize the platform with standard PC Linux distributions. Fremantle will use technologies like Upstart, PulseAudio, Open Hardware Manager, and more.

Nokia announced in late 2008 that the 5.0 release would target OMAP3 processors, meaning that OMAP2 devices such as the existing Maemo tablets would be unsupported. The Maemo developer community soon embarked on a "Maemo Reconstructed" campaign to build and maintain the free portions of the software for the older devices. That project eventually grew into Mer. Developer Carsten Munk described the effort as a proof-of-concept operating system initially, but added that it became viable for day-to-day use as well. Part of the credit belongs to the Maemo community, he said, and part belongs to Nokia itself, which has cooperated fully, offered to relicense components wherever possible, and even provide firmware images for closed-source drivers such as the tablets' power management system.

The result, as Munk put it, is that the Mer project can focus on building a "proper" distribution — eventually incorporating package repositories and regular releases. Like Nokia, the project has decided to align its base system with mainstream desktop Linux. Mer will do more than just track the underlying components, however, and will base its system on Ubuntu. That means building the same packages included in the desktop distribution, rather than low-resource alternatives like BusyBox. Although the present system makes heavy use of the Hildon application toolkit developed for Maemo tablets, Munk says to expect GTK+ and Qt support as well.

0.9 Dream

The team has been working in two-week-long development sprints since January of 2009, focusing its efforts. The most recent release is 0.9, from March 2. Flashable firmware images are available for all three Nokia tablets, as are builds for the BeagleBoard, the Pocket LOOX 720, generic x86 machines, and a bootable VMWare disk image.

Mer 0.9 runs kernel 2.6.28 and ships with a working Hildon desktop environment. Many of the desktop applications and home screen applets pre-loaded on Nokia's tablets are not installed by default, but you can add them through the package manager. Mer currently uses its own package repositories for the base system, but the tablet builds should be compatible with standard Maemo .ipkg packages. The Maemo Extras repository is enabled, opening the door to dozens of third-party packages built by the larger Maemo community, but some of the available applications fail to install due to missing dependencies not yet provided by Mer.

The core of the operating system is stable: input, display, and networking all work without trouble. Mer 0.9 is not yet usable as an everyday tablet operating system, however, due to lack of applications. The WebKit-based Midori browser is provided and works fine — but email, PIM, and instant messaging are not yet available. Munk said that the plan is to build open source applications provided in Nokia's Maemo releases; in the meantime some users may want to try the Modest email client. Maemo developers would do well to test their applications on Mer, but end users need to know that it is not ready to replace official Nokia firmware.

Nokia, GNOME, Ubuntu, et al.

In fact, Nokia's open source spokesman Quim Gil said he hopes that application developers will take a look at Mer, because having two Maemo operating systems is better for the platform. Feedback is one thing, "but it's something different if someone takes some parts of your platform, makes some changes and comes back with a proof of concept that such changes might be better for your own platform."

Mer helps "make Maemo's long tail longer and stronger," Gil said. "In order to get their work done they need to look at our code and they do file bugs and enhancement requests against platform components and with a platform integration mentality. This is useful feedback because it comes soon (and sometimes often) and also because it complements well the kind of feedback we get from users and application developers."

Gil describes the relationship between the Mer project and Nokia's Maemo team as mutually beneficial, noting that Mer makes concrete requests for licensing and redistribution changes, which are far better than blanket requests to free everything. "From our point of view it is much easier and sensible to react to specific requests with a concrete output (e.g. 'please allow the redistribution of these Nokia binaries so we can try to deliver a Maemo 5 community edition for the N800/N810'). This is also true for platform components that are actually not owned by Nokia, for instance TI's graphics acceleration drivers for OMAP2, where we are trying also to help getting a 'community edition' of such drivers."

The project is already working on a proposal to include community editions of these closed-source drivers, including firmware images fully installable on existing Nokia tablets — although it is unknown when the first such images would become available. The next Mer sprint ends on March 16, and the corresponding 0.10 release should include improvements to battery management, theme support, and wireless networking.

Mer is far from being the only Linux distribution aimed at mobile devices. Some even use many of the same stack components, such as Ubuntu's Mobile Internet Device (MID) Edition or the GNOME Mobile platform. According to Munk, Mer is different in that it is community-owned and not primarily a platform for sale to vendors. Not that it is unsuitable, he added, noting "it would be trivial to take a typical Mer image, put it on an OMAP3 board with touchscreen, put your Map software on top of it and then you have a GPS gadget ... and that's how easy it ought to be."

Maemo has been highly respected and successful on Nokia's tablet hardware, including the original Hildon interface and UI toolkits and well-integrated components from upstream Linux. As the first independent, noncommercial deployment of Maemo, Mer, if successful, could anticipate further blurring of the lines between handheld devices and mainstream distributions.