Mobile Linux at linux.conf.au

Baglady

Nancy Mauro-Flude is a performance artist who has used mobile Linux as part of a device intended as an artistic and political statement. The Baglady device is a purse with a numeric keypad on the outside. Inside, it contains a Linux-based system with wireless networking. A camera and microphone have been discreetly placed on the strap. When enabled, this device captures pictures and audio from its owner's travels, then immediately uploads them to a remote server. It allows its owner to capture the events around her, perhaps in situations where recording devices are not appreciated or allowed. The immediate-upload feature ensures that the data gets out, even if the device is discovered - at least, in places where an open access point is available.

The subversive possibilities of such a device are clear; so are the potential privacy problems. Nancy was clearly aware of those issues, but, arguably, has not worked through them completely. Others will certainly follow this particular artist's lead; expect to see more mobile devices which record their immediate environments and put the results on a server for all to see. It is going to be interesting.

Ubuntu Mobile

Canonical's David Mandala gave a well-attended talk on Ubuntu's efforts in the mobile arena. Like other such projects, the Ubuntu Mobile effort faces challenges beyond simply making the distribution run on mobile systems. Mobile systems truly are different, and, as a result, a user's expectations of the operating system are quite different. Small screens are a problem; not all applications have been written to function well when the amount of screen space is limited. Touchscreens complicate things further; David issued a challenge to developers to find ways to allow more space in menus so that fat-fingered users can use them on touchscreen-based systems.

The Ubuntu Mobile effort is actually two related projects: Ubuntu MID (for small, tablet-like devices) and the newer Ubuntu Netbook, aimed at larger devices. The Ubuntu MID work is currently based on GNOME Mobile, though David suggested that things could change at that level. In particular, he said, the Qt license change has stirred things up a bit. There is a selection of applications which are optimized for small screens. The distribution as a whole is intended for original equipment manufacturers; it is not expected that users of MID devices will be installing their own distributions.

MID systems typically use a touchscreen as their primary input device. Netbooks, instead, combine a larger screen with a real keyboard; that leads to different requirements. The Ubuntu Netbook distribution uses the full GNOME desktop - for those applications which behave well on an 800x600 display, at least. This distribution should be available in stable form at the end of the Jaunty development cycle.

David seemed to be having the most fun, though, with the new Ubuntu ARM port. One does not normally think of the ARM processor when one ponders netbook devices, but it seems that ARM is making a real effort to enable products in that area. As part of that work, ARM is working with Ubuntu to have a proper distribution ready. This effort seems to have gone pretty well; at this point, the full Ubuntu distribution is available for ARM systems. The biggest difficulty, it seems, is that ARM-based systems lack proper video acceleration. Canonical is working around this issue, though, and plans to support this port along with the others.

It seems that Canonical sees a bright future for the ARM port. While there are a number of systems available for x86-based devices, there is no real competition to Linux on the ARM processor. Windows does not run there. Symbian does, but it is not a true desktop-based system. So, any ARM-based netbook devices which appear on the market are sure to be running Linux. Canonical is doing its best to ensure that they run Ubuntu in particular.

Poky Linux

An alternative for small systems is Poky Linux, a system put together by Opened Hand prior to its recent acquisition by Intel. Poky Linux is, in fact, two different things: it is a system for building Linux-based platforms, and it is also the distribution which is that system's output. Rob Bradford, in his presentation, acknowledged that this naming practice may lead to some confusion. Still, while Poky may suffer from some ambiguity, its developers seem to make up for that with enthusiasm.

Poky Linux started as a fork of the Open Embedded platform. The developers tossed in a bunch of tools which are useful on small devices: the Clutter desktop work, GeoClue, the "Sato" user interface, the Pimlico personal information management system, GStreamer, WebKit, etc. The result is a fully-featured distribution which is well tuned to the small device environment. Perhaps the highest-profile use of Poky Linux is in the Vernier Labquest device.

Rob discussed at length the build system that was created to allow the creation of Poky Linux distributions. There are a lot of tools there which make the task relatively easy, and which, as Rob pointed out, are well suited to people who do not like to type very much. More information on how that works can be found on the Poky Linux site.

What the audience really wanted to know, though, was Intel's intentions for Poky Linux, which it acquired with Opened Hand. Though Rob didn't say so directly, the real answer appears to be that Intel doesn't have much interest in Poky Linux and is not putting resources into its further development. So, says Rob, while the infrastructure is still in place, Poky Linux has become a community project. The future of this project, it seems, is in the hands of those who use it and wish to see it continue.

Android

GeunSik Lim gave a talk outlining the internals of the Android system. Much of that talk is not amenable to summarizing here, though there were useful details which will help as your editor digs more deeply into that system. One thing that jumped out, though, was this: Google decided to create its own C library for this platform. The size of glibc was part of the motivation for this work, but the real reason, it seems, is that Google doesn't want to have GPL-licensed code running in user space. They worried, perhaps, that glibc could go to GPLv3 in the future; that, of course, would make it impossible to use in a locked-down device. So they started with a BSD-licensed libc which was then tweaked extensively for their needs. The resulting library (called "Bionic") has some big gaps (no support for C++ exceptions, for example), but it evidently suits the Android platform well.

In summary: mobile Linux is clearly one of the hot topics for this year. There are a lot of people and projects working in this area, doing no end of interesting things. It is going to be fun to see what our community comes up with.