WiFi phone enabling

[Rustiferion]

I am working in an area that has no phone coverage, but we do have an internet connection through a (satellite dish) router. I can log in to the router no problem, I can browse with Chrome & Firefox. Everyone else has phone service using "wifi-phoning", but I can't find any setting on my Sony that will enable that. My old S5 had that option, but apparently the new Xperias do not...? How can I enable it? Or do I have to install a third party app such as Skype?

[Uliwooly]

@Rustiferion

I understand the frustration but wifi calls are network dependent, check with your carrier network to see if your phone its compatible (in other words if they, your carrier network, can enable this feature). 

[Rustiferion]

I just came back from a lengthy session at T-Mobile about this. They definitely have wi-fi caslling enabled on their network, said it was "hardware dependant", meaning it has to be a feature native to the phone. After scrutinizing every options menu we could find, we both had to come to the inescapable conclusion that, for all its touted high-end gizmoditry (and high price), Sony Xperia does not have a native VOIP capability. I am SO disappointed. Alas, I no longer have my old Samsung S4, or I could use that for the week I'm going to be on this job.

The T-mobile helper suggested Google Hangouts or Facebook's version (Meet-up? or something like that). Not sure if that would do what I want, unfamiliar with either. Last option is the one I was thinking of first: Skype or some other similar VOIP app, which charges by the minute for use. Any suggestions?

Or, I could change my voicemail to direct callers to use my Gmail account... poor third option.