I have TP-Link MR 3020 with openWRT installed, i have an idea to make a communication device using just a router and a microcontroller such as arduino. the question is, is there any possibility to communicate using arduino via VoIP? as i know you need a device like a laptop or a smartphone to use voip to call each other.
i would like make a cheap communication device, i think that bring your own smartphone is not applicable in my project, and beside that you need to charge your smartphone.
Thanks in advance for your help, any advice would very appreciated.