Just a quick word on what this is for - I think Trello is a great tool for managing customer projects, but it is a bit limited in how you can keep them up to date with what is going on. "Updater for Trello" lets you decide what boards & lists to report on, then you can add your client's email and they'll get a basic summary every week. They don't need a Trello account, and can't log into your boards and start "rearranging things"
What Mom Forgot to Tell You about Remote and Freelance Work