Requirements:
1. A valid TLS certificate file for use with your SIP Server, which you can likely obtain from your IT/SIP Admin.
The file should be called/renamed sip_certs.pem
2. A TPControl SIP device.
SIP is supported in TPControl v2.6+ for Apple and TPControl v2.6+ for Android.

To add the TLS certificate for use by TPControl during TLS authentication, follow the steps below for your corresponding devices platform.

Apple devices:
Using an Apple File Manager utility, copy the sip_certs.pem file to the existing "Apps > TPControl > Documents" directory on the TPControl for Apple device.

Android devices:
Using an Android File Manager utility, copy the sip_certs.pem file to the existing "./Android/data/com.touchpanelcontrol.tpcontrol/files/certs/" directory on the TPControl for Android device.