Communication books were probably born out of our age of parenting plans and court orders and legal obligations to keep other parents in the loop.
A notebook or diary is passed from parent to parent keeping track of what happened whilst they were away. Regardless of why they came about, they are a really good idea, whether you get along with your ex or not. They are great for non tech parents and ones who would rather write than talk. Don’t expect essays from parents who never wrote before you broke up, but it’s a good way to keep to the facts. Communicating the important information with your ex is the goal.
A yearly diary format is also great for keeping track of schedules, appointments, and for writing down new events for the other parent. Medicare numbers, education Id’s, school absence line numbers, Important phone numbers, school contacts, other kids parents, sports coaches numbers can also be kept in here, avoiding unnecessary contact.
If you haven’t tried it and your communication lines are still blurry or disconnected, maybe give it a shot. Importantly, it is essential either NOTHING a child shouldn’t read gets written in there, or you agree to physically pass it to each other without the child playing messenger.
Parenting or Family organisation Apps 
Used once again originally for fulfillment of court orders etc, they have moved into use by even very together families for ways of communicating between parents during their busy lives. Most importantly, both parents, separated or together have access to the information at the same time.
As with email or texting, a digital communication technique should not open the floodgates for angry online exchanges as can occur when people have a wall to hide behind. Apps and other digitial communication can be awesome tools as long as both parents use them well.
Have a look at a couple of these apps like
However it’s done, keep on trying to communicate with your ex about your child, especially when you both have that child for periods of time. This extends to step parents and grand-parents that may care for them too. It’s one of the best things you can do to help your child adapt to co-parenting and to feel like all of you know, and care about, what’s happening in their life .