The call now feature on assignments for companies that use Gigspot say you must start the call on a desktop or laptop. When I was searching for more information on this last night, I found an article that said you can start it from your smart phone on the Mobi Audit app or by opening Gigspot on an internet browser on your phone. I tried opening from my browser and the call now button was there including my phone number and the phone number I am shopping. It does look like it would work. Does anyone know if it does actually work to call from your cell phone via a web browser?