How to block incoming calls when one of the lines (Iphone App or Zoiper App) is engaged

Question

We are testing Zoiper Primium on our iPhones, connected to our cloud thelephony exchange.

During a "Zoiper call" , an incoming call on my mobilenumber will  put the Zoiper conversation inmediately on hold and the iPhone rings to announce an incoming call. Which is annoying

How to block incoming calls when one of the lines  (Iphone App or Zoiper App) is engaged

Answer 1

Due to the regulations from Apple for third-party applications on iOS, when an incoming call comes in on the Native dialer, it is with highest priority and thus the VoIP calls are placed on hold, so the user can perform any actions the GSM call.

Comments

Nice information about this i want also to install this.