Hello,

I've been trying for a long time to get the mobile SIP client iOS app Acrobits Groundwire to work with the Swisscom SIP credentials. An older discussion did not bring a solution ([Set up SIP on Groundwire | Swisscom Community](https://community.swisscom.ch/t5/Archiv-telefonie/SIP-auf-Groundwire-einrichten/m-p/513690#M49052)) and is closed today, hence this post.

Today it finally worked and I would like to share my config here (in English, so that FR and IT speakers can also benefit from it)

How to configure the Acrobit Groundwire mobile SIP calling app (iOS) with your Swisscom SIP Credentials:

* add account, select "generic SIP Account"

* Title: enter whatever you fancy. I used "Swisscom"

* Username: +41<your fixedline phone number>, e.g.

* Password: the password Swisscom sent you via SMS for your SIP credentials

* Domain: swisscom.ch

* _tap on "advanced settings"_

* NAT Transversal: "auto"

* Proxy: fs1.ims.swisscom.ch

* enable video calls: set on disable

* Outgoing calls need registration: enable

* Display name: +41<your fixedline phone number>, e.g.

* Auth User Name: enter the "Authentication name" that you received via SMS from Swisscom, **without the @Anonym.ch** part, e.g. FR123456789

* _tap on “Done”_

That's it. 😎

Usual disclaimer: it works on my phone 🙂

Have fun!