php todo list with json database by colincarter

I need a small php script in form of a todo-list. The todo list should save the todos in a json file (no mySQL or other database please). There should be one HTML file where one can add todos. One HTML File where the Todo`s can be ticked, but no adding of todos is possible... (Budget: €8 - €30 EUR, Jobs: HTML5, JSON, PHP)