Apps TCP socket connection issues

[aliyesami]

I have my developer developing android code that connects to a TCP server but it fails to make a socket connection if the phone is active and connected to ISP, but the app works fine if the phone is put into airplane mode meaning turning off the data plan.
what could be the issue in general ?

 

[Deleted User]

When you say it fails to make a socket connection, what happens? Is there an error? Is there an exception?