In contrast, making a case is much much harder. There really aren't any good low-volume case making methods. Injection moulding is out. Machining from aluminium is an option here, but it's very expensive. There's resin casting, but that's difficult and I don't know if it's really suited to manufacture.
Honestly, making the case is 10-100 times harder than the PCB (for such a simple one like this anyway).
tinkercad.com to create an stl file, and shapeways.com to print it out.
(simple) PCB design and production is super quick and easy though, you're absolutely right.
That said, I think $10 is a good price for something like this. I, personally, would look for a corporate/industrial application that would justify a price 10x that.
i've been hassled for a cubieboard. (a single board ARM computer). They seem to hate exposed PCBs. You'd think they would have seen quite a few...
I think the board is because some power sources might go "hey I'm leaking, there is no device but I draw power!" and cut it off, but I only ever heard about it and never encountered it. My USB ports nicely power fans without ever having a data connection to anything.
Note: USB-PD changes the game a huge amount. You do need to speak USB to upgrade power there. But I've yet to see USB-PD in the flesh.
The obvious drawback would be that such device connected to charger without current limiter would burn it.
Then again I just burned a charger that had multiple sockets by connecting Samsung Galaxy Note 3 and iPad2 to it. It advertised via data lines capacity for 2A charging on all five USB sockets, but had total capacity of just 2.5 A.
if lithium batteries weren't so problematic when overcharged you could float-charge everything pretty efficiently, then you wouldn't even need a management system.
Our current way of doing things is probably here to stay, though.
A data channel isn't a data channel. USB is designed to be widely used by many industries, as such the standard has provisions for many use-cases. A battery data channel is only for the charging equipment to communicate with the battery's chipset a limited amount of parameters. The data being transferred is incredibly limited, and can thus be sanitized easier when compared to USB.
A protocol designed in such a way would also be easier to test, as the scope of vulnerabilities would be much more limited than a general purpose data channel.
Regardless, it was merely a possible answer to
> If you disconnect the data pins, how can any device (apple or anyone else) get more?"
and really wasn't meant to be a valid product or concept. Just a fleeting thought.
# cd /sys/bus/usb/devices
# for n in usb* ; do echo 0 >$n/authorized_default ; done
Of course this only prevents the USB host, you'd have to disable all USB-gadget daemons on your android phone to not have the charger tinker with the phones's data.
NOTE/added: I just realized that the main purpose this is marketed is to protect the phone's data. I'd me more worried about the computer if someone asks me to lend some juice...
which attacks the usb firmware on devices. ANY data communication and your usb device/port itself can get hacked
the usb condom might actually prevent that,
I got lot's of these things from portable usb batteries.
I'm not sure how widely implemented this behavior is for "dumb" USB chargers though, as opposed to actual hosts though.
But it might be that they want to preserve compatibility with actual hosts, in case that you i.e. want to charge on a public PC. Or they want to make sure that even if your charger is actually a disguised malicious device, you can still use it as a charger, which would be kinda ironic.
-lack of authentication
-stack errors (root on PS2 at one point)
-physical silicon bugs ( I have a broken mouse that WILL make any windows computer act funny/crash apps/crash whole Intel usb hub)
It's more about USB being implicitly trusted by the software/OS - in addition to that there's driver bugs to be exploited. Here's a few fun things you can do https://www.youtube.com/watch?v=x-7ezoFju6I
USB Condom: ~$10, available. Tends towards either a bare board with USB connectors or that board with plastic shrink tubing on it. (https://www.crowdsupply.com/xipiter/usbcondom) (http://www.usbcondoms.com/) (probably an earlier version but the same person: http://int3.cc/collections/frontpage/products/usbcondoms)
UmbrellaUSB: ~$12, available soon? More polished/finished looking than the USBCondom, got their information on voltages from the USBCondom folks (see comments in the Krebs article above). Working on fulfillment of their Kickstarter (funded July 3). (http://www.umbrellausb.com/)
ChargeDefense: ~$??, a "coming soon" page, a picture of a prototype, and maybe more in September. (http://www.chargedefense.com/)
LockedUSB: ~$20, available. More technical details available, more expensive and very blocky looking - expect it to block any adjacent ports. Technical information indicates that the single unit should work with both Apple and non-Apple devices (https://lockedusb.com/product/lockedusb-adapter-charger-fire...)
Practical Meter: ~$20, available. Protects ONLY when used with their optimized 3-in-1 charging cables otherwise passes data through. Provides a 5-bar indicator of current. (http://www.powerpractical.com/product/practical-meter) more details in their kickstarter (https://www.kickstarter.com/projects/david-toledo/the-practi...)
PortPilot: ~$60, not yet available. Much more expensive, MUCH more informative, switchable between data/no data. Includes a display showing possible and actual power draw, etc. Almost a development/diagnostic device. (https://hakshop.myshopify.com/products/portpilot)
At least 3 listed below via Amazon (2 in UK): PortaPow $7 (2 versions, www.amazon.com/gp/product/B00GC4AJOU, looks like a "beat you to market" device), and Pisen ~$1.70 (http://www.amazon.co.uk/dp/B00E8ALIYU and http://www.amazon.co.uk/dp/B00E8AJ41E).
I have several PortaPow devices too, and they work great (except for creaky connectors and plastic), so if I hadn't already the LockedUSB I wouldn't have a second thought buying their USB Fast Charge device since it's smaller and cheaper.
If you carry a USB cable around you might as well carry one of these. (But then again, you might as well carry a charger too, so I'm not entirely conviced -- but I did have use for mine once or twice so I can't really regret it.)
Which apparently signals to the charging device to output higher amperage, as cutting the data connection will make some devices only provide 0.5 amps. Not sure why this one is branded "for Galaxy", as the charging device shouldn't really matter.
There should be an option to enable data transfer, currently you have to physically remove it.
I would love to have something like this, if it enabled my devices to be read only; some usb flash drives have a physical button to enable that.
You could maybe make now that only worked for USB storage devices and only allowed reading, but it would likely be complex and have other downsides (lack of performance and compatability issues probably) that would make it not worth it.
In fact, as there is a lot more standardization in USB profiles than in IP protocols, it might even be easier. I.e. if you just inspected messages of the mass storage profile and blocked everything else, you might already get pretty far. I agree that the performance problem would stay though.
"Many public locations now offer USB charging stations, but it's a trivial task to modify one of these to allow an attacker to access your data. Int3.cc's device cuts off access to the data transfer pins on the USB port, while still permitting access to the power supply."
Way too many words on that page before just getting to the damned point.
EDIT: I retract that. From what I can tell, it's just three SMT resistors on that board. So it seems fine to me.
And this is a more "embedded" example: http://www.tomshardware.com/news/Apple-Lightning-Cable-Hacke...
I personally just carry a three way AC power splitter cube while traveling, which gives me enough ports for laptop+phone+whomever I ask to share with.
Not adding the plastic is being lazy.
One of the ports has the data lines connected, the other port doesn't, so it could be used as a USB condom.