Hi, I'm not familiar with PHPoC. What I understand, PHPoC is the IoT hardware platform that is equipped with PHPoC interpreter and uses PHPoC language for programming. So I can say PHPoC is a custom hardware, and currently, it is not compatible to any existing WiFi Shield in the market now. SO to use PHPoC, you need to use their hardware.
Correct me if I'm wrong.
Hope this helps.
Thanks.