To edit an item on your Meal Planner, simply tap on the recipe. From here, you can update the serving size, meal type (Breakfast, Lunch, Dinner), and date, as well as visit the recipe. Once you're finished, hit the "Done" button located on the upper right, and you're all set.
To quickly rearrange items on your Meal Planner, select the "Edit" option and use the three bars located beside each recipe to drag and drop to different dates. Once you're finished, hit "Done."