If you want something stronger than a six digit passcode, you always have the option of setting a strong alphanumeric password instead. Settings > Passcode > C

If you want something stronger than a six digit passcode, you always have the option of setting a strong alphanumeric password instead. Settings > Passcode > Change Passcode > Passcode Options > Custom Alphanumeric Code If you only use numerals, you can go longer than six digits and still use the numeric keypad to authenticate.