I have 30+ years of experience in writing code. My last two projects have made EXTENSIVE use of JSON data to to exchange info between server and client. One app _simulated_ a server response on the client to achieve a different code execution path. Not sure what the "real device through USB" in your project description means, but I'm very familiar with generating and reading JSON data in PHP and JAVA. I'm confident that I CAN do this for you!
I am semi-retired, I'm here to supplement my retirement income, so if you hire me you will be getting top notch experience at a really great price.
Please contact me and let's talk about what I can do for you.
Thanks,
Robert Young
Call/Txt: 408.666.2509