I use ‘appclose’ it’s free. You can call and FaceTime, if needed. But messages can’t be deleted or anything. And can also be downloaded for court if needed.
I’ve used talking parents for years. It’s like $27 a month but you can video call and do regular phone call and everything is recorded. You have text too and a bunch of other features. You can even send money through the app https://talkingparents.com
I believe there are court approved ones where you can have phone calls and text conversations that can be kept like a recording. I’d look up online “court approved co parenting app” and see what results you get