To create a new TCP Client, navigate to the app and choose 'add TCP client'.
On every TCP Client, there is a symbol which shows you if there ist a working connection to the desired device. As you have to configure every new TCP Client first, the symbol will display a red X.
Before the TCP Client can communicate, you have to enter a valid IP address in the settings. To do so, open the Parameter panel of your newly created TCP Clients and enter the IP address and the port of the desired device.
If the IP address and port are correct and a successful connection could be established, you will see a green checkmark in the display of the TCP Client after some seconds.