Technically, you can open this planner on your computer! However, you will find that it is difficult to edit your planner if you’re using a device that cannot use a pencil. I do know some people who do it and are happy with typing on it instead!
With this being said, even though I do all my annotating on my iPad, with Goodnotes5, you can sync across devices, so if I’m out and about, I love that I can reference the planner on my other apple devices – iphone and macbook.
Just make sure you have syncing enabled in Goodnotes settings!