I found out about this device after it had been released and was extremely disappointed when I found out that that it couldn’t be bought for love nor money. I even emailed them and they told me not gonna happen.
It you’re not aware of it, its a bluetooth receiver that plugs into the joystick port (9 pin) and then pairs with a bluetooth gamepad, of which 8BitDo makes several. There is a matching Apple themed one, but it’s pretty pricey.
I was then thrilled to see that they’re back! I don’t know how long for though.
Do be aware that they’ve had some issues with the analogue side of things, as released it returned 0, 127 and 255 on the joystick axis, there was a beta release which was supposed to fix this but I don’t know what happened to it, if somebody has it, I’d love to get a copy, it was on their forums.