We love to-do apps as a space all your own for creative brainstorming and planning, outside of email and other communication tools. Inside of a good brainstorming or to-do app there are no distractions or communications from the outside world, just simply a place to do your own writing and planning.
Our favorite to-do list app for Apple devices is Cultured Code's Things. It runs on Mac, iPhone, and iPad. It's a paid app, but also one of the highest quality apps out there.
Our favorite to-do app on PC (also works on Apple & Android devices) is Microsoft To-Do. This app has heritage from the venerable Wunderlist app, which Microsoft acquired a few years ago, and it's free.
Jensen Gelfond is the Founder of Asheville Digital Lifestyle. He helps people use their technology more effectively and joyfully.