At first, VoLTE will be used to deliver "Rich Communications Services" (which look like something similar to what Voice over IP/Video over IP outfits offer today) rather than completely replacing narrowband voice. It will be awhile before Verizon is willing to commit to that, due in part to LTE outages in late 2011.
On the flip side is MetroPC, which has pushed VoLTE as hard as it could.
Then there's Sprint, which will stick to voice over 1x for the foreseeable future, but routes Direct Connect over IP. Sprint's latest DC incarnation seems quite similar to one facet of RCS over LTE.
So I got the Pebble from Sprint, I'm waiting for the damn VoLTE to enable. I harassed Sprint and they said it is a limitation of the device (which they still can't explain why) and waiting is the only option. They also told me every time there is a power failure the wait for it to enable begins again.... really? Does anyone know how it works and why there is a 2-3 week lead up to VoLTE enabling? So now my voice calls drop down to 1x and I can't receive MMS when I'm on a call. No problem I thought, I'll just switch to wifi calling for now and I can still get MMS over LTE while I'm on a call. Not so fast. For some damn reason wifi calling doesn't work on my SM-G970U1 (unlocked s10e) when I'm connected to the Pebble. If I turn airplane mode on, wifi calling pops right up. If I unplug the pebble, wifi calling pops right up. That leads one to believe the Pebble is preventing wifi calling from activating for some reason. However, my dad's LG V20 has absolutely no issue using wifi calling while connected to the Pebble and can therefore receive MMS just fine. Do you have any idea what in the hell could be causing this? Is this some whack setting on the s10e which I'm not seeing? Phone has the latest updates, 911 is updated, I did PRL and profile updates. I'm stumped....
UPDATE: So I found the answer in the wifi-calling menus and googling that took me to a post here. Apparently starting in April of 2020, Sprint decided it knows what is best for you so it sets calling over the network to preferred and only if signal is too weak will it default to wifi calling. There is no visible option in the phone to change that setting. I had to download Samsung Band app to set it to prefer wifi and bam.... now it is enabled. I'd still like to know WTF the Pebble is doing with VoLTE though.