The app name in the store is “Secondary number”. To find the app in the store, you can do the following searches: “num2”, “secnum” or “secondary number”.
You can also go to the following links:
On Google Play: https://play.google.com/store/apps/details?id=com.cellact.secnum
On the App Store: https://apps.apple.com/il/app/secnum/id1215632082
The link is the same in the Israeli store, and in stores of other countries where the app is located.