DX-CP26 RS232 to Bluetooth Wireless Serial Adaper Converter Support IOSAndroidWindows Suport DB9RJ45 Interface Built-in rechargeable lithium battery (CP26 for PC)

Looks very neat but instructions are incomprehensible and very sparse. They and the software, once you find it, are largely in Chinese and don't tell you anything useful. After several days trying to get it to talk to my Android software I emailed for help - no reply. I unfortunately eventually gave up in frustration and asked for a refund. Another company, DSD Tech, produce a similar product, unfortunately with the same issues. It would probably work if it was possible to find out how to use it.