Planner works with a tablet and stylus pen and annotation apps such as Goodnotes and Notability. But you can also use it with Android tablets, phones and even computers. While you can use it with phones and computers, it won't be as ideal with tablets, the features will be limited and you may have to add text boxes manually. Again, The planner is intended to be used with annotations apps and a stylus so you can write on it like pen and paper.