First look at Android and implications for the Homebrew MyPhone

Google's new Android SDK is a lot more than a Linux distribution, its a complete and documented application framework with developer tools support. The primary language for application development is Java, with a special runtime called the Dalvik virtual machine that is designed to run efficiently on a battery powered device.

The SDK is 55MB, there is available Eclipse support.

Sample applications include Google Maps, mail, webkit based browser and the usual Phone and PIM stuff. The user interface seems to be based on a new set of Java classes, but there is also direct access to the display in C/C++ using SGL for 2D and OpenGL ES for 3D, and audio and video players for things like mp3 and H.264.

From a first pass through the docs, a lot of work has gone into this already. It looks as if it should be portable
to a homebrew phone without much difficulty, and from then on, we are likely to be leveraging a much larger community than the other open alternatives. It appears that the current state of the OpenMoko project is that they have made some progress and have a somewhat usable toolkit written in Python, but that C/C++ development based on GTK+ is painful, and documentation is scarce. It looks to me as if Android has taken the same basic inspiration as OpenMoko, but with a much more professional execution, and with a Java based developer platform.

We will be discussing this at the Homebrew Mobile Phone club meeting on Wednesday. We are holding the meeting at Mozilla's offices and will also be discussing their work on a mobile version of the Mozilla browser.

Gumstix Goliath - myPhone system board

The Gumstix Goliath open phone hardware is now available for order. There are versions with and without the Global Positioning Systems (GPS) support.

Features:	GSM/GPRS/EDGE, GPS, analog audio in/out, LCD, touchscreen controller, USB host port, 3D-accelerometer, NiMH battery charger (batteries not included) Provides full- speed USB access to the Siemens MC75 GPRS/EDGE module, the u-blox NEO-4S GPS module and one external USB device.
Connection:	60-pin Hirose connector to verdex motherboard only
Dimensions:	105.5mm x 67.3mm

I've placed my order (I already have a Gumstix Verdex CPU board), and I'm still working on myPhone case design for this board and its 4.3" touchscreen LCD. Unlike the iPhone, the hardware and software is completely open, you can do anything you like with it, and thats also the problem, the software is extremely basic at the moment. However, its about the journey, not the destination, I'm going to have a lot of fun as we build this device.

Picture of myPhone

Here are the CAD pictures of the phone, I made the rear case cover translucent so that some of the parts inside can be seen. The big dark block is a Treo650 battery, the block in front of it is the Telit 862 GSM/GPS module that does all the phone stuff... Its 130mm long and 75mm wide, quite big, but thats a 3.7" 480x640 LCD, and its easier to fit off the shelf parts inside :-)

MyPhone Making Progress and ETel Conference

I'm at the O'Reilly ETel conference this week, lots of new and interesting things happening. I've met the OpenMoko people and held the phone (nice hardware, quite compact).

Several people from the SVHMPC are also attending, we have been showing off the cases I made a few weeks ago, and I've been spending way too long on a new and much cooler case design. I've posted my design including all the cad files (this is a completely open source project, including hardware designs) to a page on the Homebrew Mobile Wiki.

Thats the main reason there have been relatively few postings in the last week...

Making a case for Myphone

I mean that in both senses of the phrase "making a case". I have produced a lump of plastic, and I have good reasons why I want to build my phone.

Here are the first parts I made, two copies of an LCD bezel with a rounded outside surface and a cutout to locate the LCD. The standing part is as it was made in the 3D printer, sideways on to get a smoother finish, and with additional "support material" that holds everything in place while the "model material" sets. The part lying flat is the same, but is face down and has the support material removed. The size is about 5" by 3" and the bezel is 0.1" thick. It took about 7 hours to print the pair of bezels, each contains 0.6 cubic inches of model material and the total including support material was about 1 cubic inch. The bezels cost $10 each to make at Techshop in Menlo Park ($100/month for membership, $10/cu inch to use the 3D printer).

This experiment went quite well, and the next step was to extend the design to form a complete top and bottom case that fit together. This was kicked off using black rather than white plastic, and lying flat, face down. This prints more quickly, but uses more support material to create the base. The base will give the phone a textured surface, which can be made shiny by dipping in acetone, and I'm hoping it will look cool, like a carbon fibre finish. Pictures of the design, cad files, and a photo of the 3D printer in action can be found at the SVHMPC Wiki, I'm updating them as work progresses. The case walls are thicker than they need to be, so the final design will use less plastic and cost less than the $40 I was charged to make this complete case.

The purpose of this build is to figure out where to put the contents, so I can mold support brackets into the design and make an attempt at a working prototype.

Why am I doing this? Some of us are attending the Emerging Telephony conference in March, and I want to have something to show. Also its fun to make things, fun to hang out at Techshop, I'm learning a lot from the 3D printer instructor, and in the end I will have a phone that evolves rather than being thrown away every few years. If I want more memory, a bigger LCD, or different trade offs in features/size/battery life, I don't have to start from scratch or accept someone else's set of compromises. That's why I call it my phone.