[robomartin]

This is neat, of course. And it also goes back to old Commodore 64 (and before) days of using audio for data in/out, including mass storage on audio tape.

I've always been bothered by Apple and the other tablet maker's choice not to include an openly usable simple serial port on their devices (or the ability to use a USB<->serial adapter). I understand the Apple "control everything" mentality. Their sandbox, their rules. Still, I can only imagine how neat it would be if all of these devices had a simple two wire serial port available without limitations. As a result of this we have to go backwards in technology by some 30+ years for simple little projects.

[VLM]

"the other tablet maker's choice"

I assume you mean android and not microsoft phone or something.

I use these for BT with android and an arduino mini. And some other devices.

http://www.adafruit.com/product/1588

aka the famous $20 Bluefruit EZ-Link

On the android side I use an app called blueterm once I connect. Its pretty boring, it just does its thing. I would imagine writing an app on the android side that does something useful and gets it on the tablet would be quite a challenge. So the BT link itself is not really the limiting factor.

Ironically in an article about programming devices, there is some weird funkiness with linux and various desktop environments and OSes such that its non trivial to wirelessly reprogram arduinos, something about toggling the DTR at the right speed and time, although the RX/TX work just fine.

I have no extensively experimented with range.

Looking at "radio shack type price markups" I think a DB-9 and hood and some cable would be a significant fraction of $20, its not like we're comparing a 5 cent solution to $20, more like $7 wired vs $20 bluetooth. On the other hand it bothers me a little to connect a $20 BT dongle to a $15 mini.

[binarymax]

I always assumed, based on my tiny amount of knowledge of the Square credit card reader, that this was possible on iOS?

https://squareup.com/reader

[lgeek]

I think it's using the analog audio hardware, similarly to this project.

[aaronem]

USB OTG, which I gather is becoming quite common on Android devices, should allow for USB-to-serial adapters with relatively trivial effort.

> Still, I can only imagine how neat it would be if all of these devices had a simple two wire serial port available without limitations.

Whatever the device or manufacturer, why compromise the design to include something which almost no one will ever care about, much less use?

[gfwilliams]

Yes, it'd be really handy... Having said that, to be truly useful you'd need to be able to access whatever it was from some API that was common across platforms. Sadly I think it's very unlikely that any simple communications protocol will get exposed to webpages, because of potential security concerns.