They have an app for $0.99, but I believe it still needs connection for all the back end task generation and stuff. Hopefully it works for you as another tool for the tool box!
Goblin tool. You give it a task you want to do and it breaks it down into smaller tasks/steps which you can keep breaking down. Also has a tone rewording tool and a tool for checking if you are taking something in the wrong tone. Super helpful for people with ADHD and Autism.