VEMS Display USB-OTG cable connection

[Sprocket]

OK so with the dodgy connection I seem to suffer with any Bluetooth adapter on my V3, what cable do I need to take advantage of the latest version VEMS Display app that can connect via the serial port.

I've searched out this http://www.misco.co.uk/product/225113/StarTech-com-Micro-USB-to-RS232-DB9-Serial-Adapter-Cable-for-Android-w-USB-Charging-Micro-USB-to-Serial-Converter-for-Android but not sure. What product was used to develop the App? There's nothing in the web shop yet ???

Thanks