I have a Tin Can for my 8 year old – it is terrific and he loves it. He can call friends, grandparents, and his cousins; it is more reliable than the DIY version I was cobbling together with a Pi and some Legos; and my spouse or parents can supervise or update it too.

What tech stack did you use before? It is interesting so many comments mention Pi when there are so many boring VOIP phones.

I wrote an app that some friends use right now. So, always interested to hear what people cobbled together!