When phone use WiFi connection, all apps can connect to internet. When it use mobile network connection, browser can connect, but apps cann't connect. Is there any settings? How can I diagnose? Phone is Sony Ericsson Xperia X8 with Android 2.1.
I think the most interesting is you APN and Operator. It could be that only http traffic is allowed (port 80 and 443 for https) or some similar limitation. Check you operators support page for details.
In my country there is one operator with whom we've same behavior. They have given us two different apn. With first only the browser works, exactly like you have said. With second everything works.
If your operator has different apn for using Mobile internet in Computer, try that apn. This works with one of the operator in my country but not sure if this will help you.