My granddaughter is over for a couple days visit, and we decided to go out and play disc golf. I thought it would be a god idea for her to tuck a phone in her pocket and practice calling her dad, her mom, and me.

We practiced hitting the power button, sliding to the left and to the right, finding the contacts icon and finding her parents and me. Got great cell coverage in NWATL area.

I think I need to explore a few of the games next. But Ubuntu Touch on a OnePlus Nord N10 on the Mint network is 8 year old granddaughter approved. Well, we'll need to check messaging next. Granddaughter texts are very emoticon heavy. We haven't checked that out yet.

@rocket2nfinity uNav worked great last trip. I just clicked on my Home location and GPS kicked in very quickly. I'll need to check your method as well. I was out and hadn't researched, so just tapped things. Anyway, PodCat worked just fine for playing Good Hang by Amy Poehler while uNav gave me directions home. And dekko did great for email notifications.

I decided to forward my primary mobile number to my Ubuntu Touch phone while running errands today. Forwarded calls, powered up my phone. Must have hit something while transporting the phone before it was fully booted, as I got stuck in a boot loop. I put it away while I went about my errands. Researched when I got home, and all it took was hitting power and sound up at the same time.

Oh well. Phone is u and working. I can forward my calls. I don't see an option to forward SMS messages. I'll research that a little more, as I'd rather not swap sims based on what physical phone I want to use as primary.

And I was able to receive a picture. The first attempt failed. I hit the red download button and got it on the second try. I might spend some time trying to figure it out, but am okay with it for now. (maybe because I have an Internet SPN and an MMS APN? Maybe because I am connected to both wifi and cellular with an LTE connection?)

I compared APN settings to my Android phone that is also on Mint Mobile. This worked for me, and let me send photos.
So, here is what worked for me:
Name: ultra (all lower case)
APN: wholesale (all lower case)
MMSC: http://wholesale.mmsmvno.com/mms/wapenc
Proxy: leave blank
Proxy port: leave blank
User name: leave blank
Password: leave blank

On my tests, the picture did not go through the first time, it failed. I hit the red failed icon to try again - and it worked on the second try. Not sure why. But I'll take it.

I asked my son to try sending me a picture. Once he does, I'll know if receiving pics works. But I'm calling it resolved.

I forgot to add that wifi is enabled and my phone goes between L and 5g depending on where I am in the house. But I did not turn wifi off.

I'm not on Telegram, but probably should be. Thanks for the head's up.

So, I thought and thought and thought. And decided I am missing something extremely obvious. I have two Mint numbers for me - one for my Android phone, one for Ubuntu Touch. And I have a 3rd for my son's iPhone. And a fourth for my wife's iPhone. They are all on Mint. MMS works on all of them except my UT phone. Maybe I ought to just look at the APN settings on one of the working phones and compare it to mine.

So, here is what worked for me:
Name: ultra (all lower case)
APN: wholesale (all lower case)
MMSC: http://wholesale.mmsmvno.com/mms/wapenc
Proxy: leave blank
Proxy port: leave blank
User name: leave blank
Password: leave blank

On my tests, the picture did not go through the first time, it failed. I hit the red failed icon to try again - and it worked on the second try. Not sure why. But I'll take it.

@gpatel-fr I can't receive pictures my son sends to me. I can not send pictures taken with my UT phone. Neither works.

I have a OnePlus N10 Nord 5G running 24.04. It's working pretty well, but I can't seem to get MMS working. I can't send pictures to my son (gotta share the home made sourdough bread pictures and photos of birds at the feeder!).

This is what Mint Mobile site says to use:
APN Settings

Name – Mint
APN – Wholesale
Proxy – (leave blank)
Port – (leave blank)
Username – (leave blank) 
Password – (leave blank)
Server – (leave blank)
MMSC – http://wholesale.mmsmvno.com/mms/wapenc
Multimedia Message Proxy – (leave blank)
Multimedia Message Port – 8080
MCC – (do not change default values)
MNC – (do not change default values)
Authentication Type – (leave blank)
APN Type – default,supl,mms,ia
APN Protocol – IPv4/IPv6
APN Roaming Protocol – IPv4/IPv6
MVNO type: GID
MVNO value: 756D

I don't see an option in the GUI for a lot of these settings, but I did set Name to Mint, APN to Wholesale, MMSC to http://wholesale.mmsmvno.com/mms/wapenc. I left proxy and proxy port blank.

When I do this, my phone takes forever to start up and I have to force a boot (hitting sound up/sound down/power at the same time and holding for 10 to 20 seconds).

Anyway, sending pictures is not working, and a simple boot fails.

Thanks! I turned off RCS in Google for my sim. I also tried turning off wifi. And blanked out the proxy port setting. Still no luck sending a picture. I'll open a second topic asking for any Mint Mobile users to share their APN settings for MMS, just in case I might need to go beyond the GUI settings and edit via terminal. But for now I swapped sims again. Moved my primary back to my Pixel 6a running android and my secondary to my Ubuntu Touch phone.

But the phone did pretty close to great using it as a primary yesterday. No problem sending and receiving calls while out and about. No problem sending and received texts (without images) and forwarding my purchases to my wife as we track what was spent and where it was spent). No problem selecting a Podcast and playing while doing errands. Currently enjoying The Guardian - but lots of choices. uNav worked just fine. I saw that when I clicked on my favorited home address, GPS kicks in much more quickly. No problem installing uTorch to use my phone as a flashlight at night. Web Browser worked just fine, but some sites gave me warnings about it being unsupported. It just worked anyway.And KeePassXC worked like it should, no issues. I can't edit entries, but I normally do that on my desktop, then copy the database out.

So - keeping the phone. Will watch for MMS working. As I did miss a text from my son where he sent a picture of an award he earned at work, and my response was to please e-mail photos. That was not the right response - once I saw his text on my wife's phone (he sent it to both of us), I properly congratulated him.

Anyway, will watch for MMS and will try to tweak settings. But the phone was very close to doing what I needed it to do.

@rocket2nfinity the sim was in an android phone. I'm not sure how to turn RCS off, but will look it up. Wifi is on. I don't get a good signal in my home, so I call over wifi, unless I'm out.

For MMS I used these settings:
Name: Mint
APN: Wholesale
MMSC: http://wholesale.mmsmvno.com/mms/wapenc
Proxy: left blank
Proxy port: 8080 (not sure if this should be blank)
User name and password are blank

I'm not sure how I should configure nternet, or just leave it alone.

Sending a picture fails.

I have a OnePlus 10 Nord on Mint Mobile. I can send and receive regular text-based messages (just regular text). When my wife and son send images, I get a "Could not fetch the MMS message. Maybe the MMS settings are incorrect..."

Is there anything I need to tweak to be able to view pictures, screenshots, gifs, jpegs, ... when receiving text messages?

I am on Mint Mobile in the US.

you were right
port 587
encryption: starttls
authentication: plain

it's working!

(now to set up my fastmail account)