DD8 has a Kindle Fire Kids, but has access to my adult profile (under supervision) for certain apps that are not available on the kids' profile (like, frustratingly, YouTube Kids).
She chats to her real-life friends on AnimalJam, using their Safe Chat function. Because of homeschool plus enforced regular self-isolation, I would like her to have access to a bespoke messenger app, but one that I can log into regularly to check her usage. She is very grown up and trustworthy, but I would still like to limit a) who she can chat to and b) check the content of her messages occasionally.
Are there any recomendations for kid-friendly messenger services that work on the Kindle Fire?