The MizuDroid SIP Softphone is a free, unlocked, professional SIP softphone for Android devices.

This app doesn’t include any VoIP service. You can configure it to be used with any SIP server or service provider.

The app supports both VoIP and SMS services. You can set it to use your phone number and your contacts for making and receiving calls. You can also add contacts and set the VoIP service to use your phone number and their phone numbers.

You can use the app to make calls to mobile/landline phones.