I found this on a US Amazon forum where a similar question was asked. As I read it, you just need a friend with a smartphone to complete the initial set-up. After that, your Echo Dot will work independently and your friend won't be troubled by unwanted messages either:
"Yes! It is possible to connect an Echo Show with just internet and a flip phone ( as long as you have a friend or family member with a smart phone with the Alexa app.- just for set up purposes only). ). We purchased the Echo Show for my 86 year old mother-in-law so that she could see the grandchildren and great grandchildren as she lives in Florida and we live in Pa. There was an Amazon Rep at Best Buy who assured us this was possible as long as my mother-in-law had (or created) a free Amazon account which we did for her. But after struggling numerous days and reading all of these answers here, we were about to attempt to return it. As a last ditch effort I called Amazon and within a half hour we were video calling. And it works great! Here are the basic instructions:
First we set up the Echo Show by plugging it in and connecting it to my mother-in-laws WIFI.
(Easy - just follow the prompts).
Second - I went on MY cell phone and had to “sign out” of my Amazon Alexa app. (You do this by opening the app, then tap on the 3 horizontal bars in the upper left corner, scroll down to settings, then scroll down and tap sign out. Easy!
Third- “Sign In” as my mother-in-law with her Amazon account and password ( on my phone).
It will then ask for a phone number. I put in my mother-in-laws cell phone number (which is a pay as you go flip phone). It sent the flip phone a text with a 6 digit code which she read to me.
And this was her one and only text she ever received. We didn’t know her phone could receive texts, but apparently all cell phone are capable. It probably cost her a quarter.
I entered this verification code and there was her account!
Fourth and final step: While still signed in as her, I tapped the 3 horizontal bars in upper left corner of app, scrolled to and tapped contacts, then tap the 3 vertical dots in upper right corner, then tap add contacts. I added myself and siblings and grandchildren - just names and cell numbers. Be sure to hit save after each entry.
Then I signed out of her account and entered in to mine. I had to go in to my contacts and add her to mine in the Alexa app. It’s not enough for her to just be in my contacts. She had to be added in my Alexa app contacts.
Then to call simply hit the “communicate” button (conversation bubble at bottom), tap call, choose her from all your contacts, and scroll down and tap Alexa Video Call.
I did all this from my home! It really is easy. You can also call her home phone or flip phone from here, but that’s not why she has this. Once you are both in each other’s contacts (on the app) she can simply ask it to call me and it defaults to video call. I just have to accept or decline when it rings. The picture quality and sound are much better than I anticipated. She loves it!! My hats off to the Amazon rep I was able to speak to in person."