[linuxkernelnewbies] The Android Dev Phone 1 [LWN.net]

[Peter Teoh]

http://lwn.net/Articles/311715/ The Android Dev Phone 1 [LWN subscriber-only content] By Jonathan Corbet December 29, 2008 Your editor's long-suffering spouse will attest that gadgets are never in short supply in the house. Many of them pass below her interest, but a new one has come in which has attracted attention throughout the household: an Android Dev Phone, otherwise known as the fully unlocked version of the G1 phone offered by T-Mobile. This phone is certainly a fun toy, but it has the potential to be a lot more than that. The details of this device have been well publicized for a while now. It includes a nice touchscreen display, QWERTY keyboard, GPS receiver, accelerometer, 3.2 megapixel camera, and more. The whole thing is powered by Google's Linux-based Android platform. The Dev Phone is essentially the same device as that sold by T-Mobile, but with a crucially important difference: it is unlocked in all senses. This means not just that it can be used with any mobile carrier's SIM, but also that the base operating software has not been locked down. This is a phone for which the entire system can be rebuilt and replaced at will. The Dev Phone thus joins the OpenMoko Neo Freerunner on the very short list of truly open mobile handsets. This device, though, has the advantage of being a bit more of a finished product with what appears to be a rather stronger software development team behind it. It also, for what it's worth, has some nice hardware capabilities that the Neo lacks: quad-band GSM, 3G (though not on the bands used by your editor's carrier, alas), keyboard, etc. Your editor believes that it will be a successful product. Over the course of the next few months, your editor plans to dig into this device and report on what he finds. How open is the device really? What does it take to put a new kernel onto it? What might it take to put a different operating system onto it altogether? And, in general, how does this whole Android thing work? Assuming that he does not brick the device early on, your editor hopes to get a real sense for what can be done with this device, how close its software is to what we normally think of as Linux, and where it might go into the future. It should be a fun project. First, though, one has to get through the stage of simply playing with the new toy. So the rest of this article will be a user-level review of sorts. The hardware: it feels generally solid. The device is larger and heavier than handsets your editor has used in the past, but that is to be expected. The keyboard works better than one might think given its size; even your relatively fat-fingered editor is able to type with reasonable speed and accuracy. The vibrator lacks strength. The camera seems to take nice photos (for a phone camera), but it is exceedingly slow. As with most color-screen devices, the display is entirely unreadable when the backlight is off. A nice touch with this phone is an indicator LED which blinks when the phone has something to tell you - an unread text message, for example - but the use of the LED seems to be somewhat inconsistent. Your editor has yet to get a sense for what the battery life would be in the absence of children playing with the device all day long. Complaints about battery life can be found on the net, but it appears that the phone should be able to get through two or three days of moderate usage where the GPS receiver is off most of the time. On the other hand, if you let your kids use it to mess around on video sites, the battery runs down relatively quickly. On the software side, this phone gets off to a bit of a rough start. It first requires the user to configure the phone to access data service from the carrier, a process which must be done by hand if that carrier is not T-Mobile. Your editor's last new phone recognized the carrier from the SIM and handled this task automatically. More annoying, though, is that the phone requires the creation of a Gmail account as part of its setup process. The fact that one does not have - and does not want - such an account is not relevant. So now your editor has an entry in the Gmail account database which will never be used. That, of course, ties in to why Google has gotten into this exercise in the first place. There are many features of the Android platform which are designed to tie the user in more closely to services provided by Google. Some features, such as the calendar, are really just an extension of the online offerings. The phone wants to sync the contacts list to...somewhere...and turning the feature off leads to unpleasant behavior. It is possible to use many of the features of the device without connecting back to the Google mother ship, but it's not the natural mode of operation. Another example is email handling. There is a separate icon for Gmail which just works; that application offers the features (such as threading) provided by that service. One can run a different mail application to connect to a POP or IMAP account somewhere, but it's a separate setup process. Later, with luck, one discovers the improved K9 client, which must be installed separately and which requires one to go through the setup process again. Even with K9, the non-Gmail mail client is not what it should be. There is no threading of messages, many basic commands (refiling messages, for example) are missing, etc. Then there's little problems like refusing to connect to a server if it doesn't think it can trust the SSL certificate and failing to authenticate if the user's password contains special characters. One assumes that this client will improve, or that other clients will be ported to the platform, but, for now, it doesn't seem to be a priority for the Android developers. More generally, though, the Android software is pretty slick. A fair amount of thought has been given to how interaction should work on this kind of device. Once one gets used to a few specific differences (holding a finger on an item on the screen for a few seconds often brings up otherwise hidden options, for example), navigating through applications comes fairly naturally. Only in some cases do inconsistencies pop up - some applications have different notions for how to zoom in and out than others is one that your editor has noticed. As a whole, the interface comes across as polished and attractive. That said, use of the display could be improved. On a small display, there will always be a certain tension between getting enough information on-screen and avoiding the creation of headaches through severe eye strain. Different users will do better with small fonts than others. But if Android offers an option to configure default font sizes, your editor cannot find it. So it becomes necessary to manually zoom almost every web page, almost every email, etc. to get a sufficient amount of information onto the screen. That gets a little tiresome after a while. The "Android Market" offers a wealth of applications, most of which are available as free software or, at least, in a free-beer mode. When browsing applications, one runs into the Android security model, which is oriented around a long set of capabilities which can be granted to applications. A program which needs do things like access the net, obtain location data, change hardware settings, etc. must declare the capabilities it needs; these are then presented to the user at installation time. Most users will probably just say "yes," but it is worth taking a closer look. Your editor decided to decline the installation of a Mahjongg game after being unable to figure out why it was asking for full network access. Beyond the inevitable games (including one of the worst Tetris implementations seen in a while), there is a wide variety of available applications. The "Locale" tool makes up for the (surprising) lack of the sort of "profile" feature found on almost every handset your editor has ever seen; it perform tricks like using the GPS receiver to automatically change profiles when the phone enters the office or a theater. The "bubble" application (shown on the left) turns the handset into a portable level. There's no shortage of "smart shopper" applications, most of which can read a barcode using the camera and look up prices for items. There is a "power manager" which attempts to configure the device for optimal power use in a number of situations; it provides a basic profile functionality as well, though the user should be prepared to spend some time configuring the options into a workable form. There's plenty of travel-oriented applications which will fetch weather reports, currency rates, or call a taxi. One notable omission, with both the base phone and the available applications, is voice over IP functionality. This handset should be able to do VOIP beautifully, but almost no such functionality is available. There appears to be a tool for Skype users, but that's about it. There are a couple of applications that are of particular interest to your editor. ConnectBot is an SSH client which works surprisingly well; the developers are clearly working toward the creation of a tool useful for people logging into Linux-like systems. And the terminal emulator provides that all-important feature: a shell prompt on the device. Even more fun, on the Dev Phone, a simple "su" with no password will yield a root shell. Playing around on the device, your editor sees that the ARM processor provides a mighty 383 bogomips. It appears to have a little over 100MB of usable memory. It's running a 2.6.25 kernel (known to be heavily modified) with a single loadable module called "wlan." And so on. As useful as the keyboard is, trying to use it to type commands at a shell which lacks a history mechanism gets painful after a while. Time to go looking for an SSH server. There are other useful applications, of course, such as the one which actually makes phone calls. Like the others, it lacks perfection, but one can only assume that, on a platform driven by free software, that imperfect applications will be improved or replaced. How easy it is to do such things is part of what your editor intends to find out in the coming months. Stay tuned.