Go to https://www.zoiper.com/, navigate to “DOWNLOAD,” and download the version you need.

Zoiper versions

The download should start automatically after 10 seconds. After downloading, proceed with the package and follow the steps required to install the software. Then, open the Zoiper application on your Android smartphone and enter the SIP details in several steps (authentication and proxy are not required). Zoiper will perform a test (this may take some time) and then notify you that the softphone is active.

Installation on iPhone

For iOS devices specifically, follow these steps:

Press the plus icon in the top right to add an account.

Zoiper iPhone step 1

You will be asked if you already have an account. Choose Yes.

Zoiper iPhone step 2

You will be asked if you want to do a manual configuration. Choose manual configuration.

Zoiper iPhone step 3

Select SIP account as the account type.

Zoiper iPhone step 4

Then, you can fill in the settings.

Zoiper iPhone step 5

As the final step, under network settings, change the transport setting from UDP to TCP.