This is an excellent product for breadboarding projects. It provides full Arduino capabilities in a narrow DIP form factor that allows 4 connection points per Arduino pin, plus 4 rows between headers for neat interconnects between other components. No more rats nests of long wires, and very convenient to use with scope probes. The multipurpose LCD is a nice feature. The price seemed high initially, but after allowing for the amortization of engineering costs over a small production run, it is excellent value.
I do not know how the castellated holes on the PCB are supposed to be used, since there are SMD components on the underside of the PCB, and be sure to read the errata sheet explaining the inverted labeling of the 5V and A7 pins.
One day I was working on a breadboard project, and I had an idea for simplifying my usual setup for power, indicator light, etc. I started drawing up plans for it, then decided to search online for a similar product first. This thing does everything I wanted and more. I'll probably never use a breadboard without one again. So far I haven't had a chance to try out the USB functionality - it's just a little power supply unit for me - but even without that it was worth the price.
There isn't really any documentation that I could find, but it's self explanatory.
I find it very convenient to have the serial port and the reset button on the board. I have not yet used the rechargeable feature, still looking for a good battery to use. Right now I use one of those USB batteries.
Talk about an obvious item to have.. I haven't seen these before.
I grabbed a couple and I tell you they make a huge difference on board space! I soldered the pins on mine (I think you can have him do this for you?) I got mine with 220 Ohm resistors so they work well with 5/3.3V. Those are optional and you can get different sizes. If you're curious about what size you should get ask AtomSoftTech.. very helpful, very prompt.... the speed of delivery was super quick even across the US.
It's amazing how much you don't realize 4 LEDs and their current limiting resistors take up on a board. I tried to upload an imagine but it's not working out with Tindie for some reason despite just recently uploading one for another project. Perhaps cost of product per MB of imagine isn't working out? :D Trust me these will save you a ton of space and they're much easier than digging for the right resistors.
I have a couple breadboard supplies but after I got this one, they've all met the bin in the back of the bench.. this breadboard buddy supplies voltage just like all the other ones out there.. 5V or 3.3V, powered off USB.. cool, but the real feature is the USB to serial converter! Excellent! A maker/hacker dream come true.