Cell phone suggestions?

Sohenc, I read your profile, good heavens you had your hands full with you Mom.

As one ages, their eyesight becomes not as clear thus cellphone are hard to read even if the font is placed at the highest level. Also, one's hearing is not clear, as you have already noted on your profile, thus a cellphone is terrible to use as the clarity is like talking to someone in a metal trash can. Landlines are so much clearer, especially landline to landline.

Being your Mom is now in a nursing home, the rental of a landline phone would be so much cheaper than the cost of cellphone/service. I noticed you paid for a lot of things for Mom over time, that's a big bite out of your own savings.

i am in my 70's and am computer/internet savy, but I found cellphones [the worst one I had was that made for seniors] not all that user friendly. The KISS acronym does not apply.

Maybe this might work www.agingcare.com/products/big-button-picture-phone-204799.htm

Expecting mom to learn anything new at this point is probably a bad idea. In addition to having lost the ability to make and hold short-term memories, she’s probably unable to hold a sequence of information long enough to complete linked tasks, such as picking up the phone and remembering her intent to use it to call a specific person. You may need to rethink this.

Maybe someone else has posted a workable idea, but what you want mom to do will probably frustrate both of you.

From what you say it's time to take away the phone and switch to something you can set up to make incoming calls only. Your mom doesn't have the capacity anymore to manage her phone.
Consider if you should deactivate her SIM card-most cellphones can retain an internet connection to run a browser, and the camera will still work, but the ability to make calls and receive texts will go away-you need to check w/ the phone provider or do a Google deep dive. https://blog.rottenwifi.com/can-you-use-wifi-on-a-deactivated-phone/

A tablet might be a good optionto use for setting up incoming calls, but I think one of the problems you're going to face is that any new device might not be usable since there's no ability to retain new information. People with dementia can use things they've used for a long time because they retain the rote actions to use those things, until they lose that too. I would test the waters with anything new to see if she can even figure out how to use it. Maybe someone has a tablet you can hand her to see if she can navigate it? Keep in mind that most handheld tech devices are very icon heavy-at some point even familiar icons won't make sense, but you'd have more success if it looks familiar to her phone set up.
I had heard the Amazon's echo Show can be set up to take incoming video calls only, not sure if a Kindle Fire can. The Grandpad would be a good option as well, but perhaps pricier.
Definitely see if you can pick up a refurbished version. If she's used to having her phone that might be the thing she looks for and she won't be able to migrate to a tablet.

There might be some options here:

https://www.alzstore.com/picture-memory-phone-dementia-s/1843.htm

We had to take away my MILs flip phone because she was nuisance calling everyone in her contacts. We recently got her a land phone with picture buttons but she never adapted to it. Just have tempered expectations as you invest in "solutions" that she may soon forget.

There was another post recently about a product called GRANDPAD
I know nothing about it. I never had concerns like this with my Husband
I do know that probably very shortly your mom(?) will probably lose the ability to use the cell phone.