Dice apples into ½-inch pieces. Place in a saucepan with water, lemon juice and sugar over medium heat. Bring to a boil, then turn the heat to medium-low and cover. Cook for 15 minutes, checking frequently to prevent burning. When the apples are soft, use a stick blender or potato masher to break up the apples to a smooth or slightly chunky texture, as you like. Stir in the cinnamon.