I have been using Mobile Chat Conqueror on my 3650 for a while. It supports text chat, photo, and Push-to-talk functions. But recently, I cannot connect to the server anymore. I have no problem using other services that needs GPRS connection. This happened before and then came back to normal with no clear indication. I do not know it is because of the software/server or it is my carrier. I am in the US and using T-Mobile. Anyone uses a S60 phone or UIQ phone can give it a try?
Their website is: http://www.ydlb.com/eng_index.htm Click on Software Download on the right side of the web page to download.