Given that Broadcom originally designed the BCM2835 for smartphones, this could be said to be an actual "intended application" of the SoC. :)
$15 for a 2.5Ah battery is rather overpriced, however - as are the rest of the components like the screen and DC-DC. I found the SIM900 on eBay for $15, the DC-DC for $1.50, and ~ $5 for a battery of similar capacity. He could've put the whole thing together for <$100. Having done some electronics sourcing in China really changes your perspective on cost... amusingly enough, there was actually an iPhone 3G clone a few years ago called the PiPhone.
It's an interesting project but practically speaking $100 (no contract) can already buy a pretty good smartphone these days... and one with a more "unofficially open" SoC too.
I've used http://www.dx.com quite a bit. Prices are really, really low. Shipping is free. However, you may have to wait two months for your products to arrive.
Since most of this stuff is based off of open source hardware it's pretty much identical to the name brand stuff. So it pretty much comes down to a cost/time ratio consideration when first starting out. Before you know it though, you will have quite a large collection of parts built up.
Also remember you can hit garage sales, recycle yards, and thrift shops to find a lot of old hardware that you can salvage valuable parts out of for less than the price of the parts themselves.
Having ordered lot's of cheap prototype/evaluation boards through dx.com/ebay/aliexpress.com, I can say for sure, that quality does differ.
Seed and co have higher standards for soldering/reflow quality, wheras random factory churns out boards, probably even not doing any sort of testing apart of "hmm, looks connected".
That being said, most of the stuff still works fine despite shobby soldering and cheapest parts they could get at the market that week.
"It's an interesting project but practically speaking $100 (no contract) can already buy a pretty good smartphone these days... and one with a more "unofficially open" SoC too."
Does that smartphone with a "more unofficially open" SoC
boot from SD card?
Is it OS agnostic?
I would actually be willing to pay more than the going rate
for a "smartphone" that that allowed me to use my own
bootloader and my own choice of OS, and one with no ties
to search engine ad sales companies or the like.
I just want a handheld computer with a decent enclosure
and which can be controlled with time-tested, open source
drivers.
It does not need to have impressive specs, just a small form
factor and easy to control with any open source OS.
As soon as they have something that boots BSD,
where starting the graphics layer is optional
and it has decent networking, I will definitely
purchase one of these. I wouldn't mind a little
FORTH, too.
NetBSD and FreeBSD were already ported to Neo Freerunner few years ago, and you actually don't have to start the graphics layer on any OS. You can also already use whatever programming language you like, it runs just a standard operating systems like your desktop do, just compiled to different cpu arch (arm).
If there's any BSD running on OMAP3 boards like BeagleBoard, then running it on Neo900 will be trivial and you can do it by yourself. Any documentation needed for more specific support will be public, so you can do that by yourself as well.
also, Openmoko is long in the past. Long live OpenPhoenux! :)
RPi doesn't allow you to use your own bootloader. You cannot even start it without closed blob, so it's in contradiction to your previous requirements.
I have yet to find a device that meets all my requirements (some of which I did not mention).
In RPI's favor I will say that 1. it is not "in development" but is "on sale" and 2. it does not come with Linux preinstalled. Letting users choose their own OS and not limiting the choices is a start in the right direction. There is of course further to go. Alas, it does not stop at the bootloader.
So, where do you recommend purchasing the device(s) you mentioned when they eventually go on sale?
Neo900 probably won't come with any OS preinstalled, maybe except some Debian based BSP which you'll be encouraged to replace with OS of your choice, as it won't be supposed to be actively used - it will be there for easy testing if all hardware works as it should.
It is a small project with very small target audience (currently about 350), so it won't be built to shelf, as there's simply not enough money to do that; therefore if you eventually want it you should express your interest now by donating at least 100 EUR, so you'll be counted on component sourcing. Donation will act as a rebate on the price of the device when it's out (in few months).
More details: http://neo900.org/#donate
Where to buy? Straight from its manufacturer, of course.
There's also GTA04 - http://gta04.org/ - which is already out for few years, but now it's unfortunately hardly obtainable and it seems like there's not enough interest from customers to do next production batch (well, most of potential customers probably were stolen by Neo900 :P). Neo900 is based on GTA04 and produced by the same company.
And of course there's also old good Openmoko Neo Freerunner, which despite of being massively underpowered, meets all requirements you mentioned. It should be still available at some retailers, like Golden Delicious Computers, Pulster or IDA Systems.
Also, you might want to look at MIPS-based Qi-Hardware Ben NanoNote. It's not a phone, but it also meets your requirements and it's available (though supplies seem to be near end, so you better hurry if you decide that you want it. AFAIK Pulster and IDA Systems still have it, but you can count remaining units with hand). I don't know if someone launched any BSD on it, but I can't see why it shouldn't be possible.
So, to make it clear, every device I mentioned so far in all my comments, except Neo900, already went on sale. With Neo900 it's a matter of few months.
From future devices also worth noting, there's DragonBox Pyra, an OpenPandora successor, which will also provide optional modem (the same like in Neo900 btw - those two are actually sister projects, sharing some developers).
The only thing Raspberry Pi is better than any of those devices is price, but when you'll count money and time spent on making Raspberry Pi an acceptable option when operating on battery, this probably won't be true anymore.
Off topic, but I think it is a good opportunity to spread the world about it: PiPhone is also an open source tool build by La Quadrature du Net in order to allow citizens to call their representatives (in France and the European Parliament).
He should really consider smoothing it out a bit and selling it as a beginners' kit somewhere.
I would love to give my little nephew something like this where he would have to assemble all the separate parts and do some basic Linux configuration. Perhaps Adafruit could help him out with that?
HN strongly prefers original sources. The original url [1] was just a summary of this one, with a video.
Edit: The traffic seems to have killed the server within seconds of the URL change, so I'll change it back for now. If davidhunt.ie comes back, would someone please let us know?
Edit 2: Trying again. Edit 3: Down again. Probably best to give up.
PhoneBlox-style fancy modular smartphones are an interesting prospect, but I really wish there was a simple replaceable-parts phone design based on ordinary development-board-style PCBs. Make it about 25mm thick and then it would be somewhat viable to carry around as a nerdy but genuinely usable phone, while still having enough internal space to be based on replaceable PCBs without too much pressure to miniaturise. Such a standard would have lots of utility: as a testbed for commercial phone development, as a place to experiment with new hardware or software for phones, as a phone (or just a gadget) incorporating niche (or "niche-of-one") hardware or software you can't get in a commercial device, as the equivalent of a self-build PC for enthusiasts.
I'd love to put my own little cell phone together, but in my area the only reliable provider is Verizon, and I haven't been able to find a CDMA module for Pi or Arduino or otherwise.
You might want to try posting this question on specialist electronics subreddits and forums like r/electronics, r/rfelectronics, r/electronic_circuits/, r/hwstartups and r/hardware. So I guess my advice would be to treat it like a numbers' game :). There's bound to be someone out there who can help you.
This is the first I hear of these Sim900 boards. Are there any other boards like it? Possibly 3G compatible models or slimmer versions with just soldering leads instead of jacks? I guess you could easily remove the jacks anyway if you needed to.
Combined with some of the slimmer boards out there (like one of the many old Allwinner sticks or Gumstix), this could actually be used to build a real open source DIY phone platform.
Some Huawei data sticks carry phone-capability according to their "Mobile Partner" software (there's support for it in the disabled modules. Mobile Partner is a pile of shit but sometimes it's actually useful).
I do not know however which exact sticks can do this.
There are lots of them. Just look at what GTA04 and Neo900 are using (Option and Cinterion). Such project can't accept closed baseband being highly integrated with main CPU and RAM like most of modern smartphones do, so they use ready 3G/LTE modules to move it out as a USB peripheral in CPU perspective.
Heres to me hoping that I can have a tablet which I can use to documents and use rsync to keep the documents synchronized with my workstation. Have been waiting for the kde vivaldi tablet. Also unclear if the latest bay trail tablets will run linux without issue.
Oh yeah, that's a good question. I've helped people with RPi audio projects before and getting external microphones to work consistently has been one of the biggest pains.
Now there is a video. In the video, he plugs a head set and a microphone into the SIM900. The audio out, 2 usb ports, and ethernet port are unused on the Pi.
$15 for a 2.5Ah battery is rather overpriced, however - as are the rest of the components like the screen and DC-DC. I found the SIM900 on eBay for $15, the DC-DC for $1.50, and ~ $5 for a battery of similar capacity. He could've put the whole thing together for <$100. Having done some electronics sourcing in China really changes your perspective on cost... amusingly enough, there was actually an iPhone 3G clone a few years ago called the PiPhone.
It's an interesting project but practically speaking $100 (no contract) can already buy a pretty good smartphone these days... and one with a more "unofficially open" SoC too.
The antenna sticking out of it is the best part.