I’m trying to develop an android app which should be able to connect Lifx A21 lightbulb with local wifi router, is there a way to do this without Lifx Smartphone App.
Unfortunately the protocol for telling a device what wifi to connect to isn’t part of our public API.
Sounds like time to use something like wireshark to sniff some packets.
I would start here, but switches by design make it hard to sniff data - ideally you need to monitor FROM your switch/router. Knowing the local network IP address of your phone and the light should make filtering that conversation from the general network noise easier.