Credit: Hadlee Simons / Android AuthorityThat dialpad on your Samsung Galaxy phone isn’t just for making calls. Type the right combination of numbers, asterisks, and symbols into it, and you’ll unlock menus and features you had no idea existed.These are MMI (Man-Machine Interface) codes, and with them, you can pull up your device’s IMEI, hide your caller ID, clear old system logs, test almost every piece of hardware on your phone, and do a lot more.