Original: Its sequels, Speaker for the Dead, Xenocide, Children of the Mind, and Ender in Exile, follow Ender's subsequent travels to many different worlds in the galaxy. Also the subsequent book, A War of Gifts takes place during the same time period as the original.
Simplified: The book takes place around the year 2135, and its sequels Speaker for the Dead, Xenocide, Children of the Mind, A War of Gifts, and Ender in Exile: Ganges follow Ender to different planets as he travels far into the future.