RobTop has done multiple face reveals throughout his time as the sole Geometry Dash developer. Here are all known pictures of him.
Note that these are pictures that RobTop himself has shared and they are public information. Dashword will never share private information without extra approval.
First ever picture of RobTop.
RobTop's second face reveal, shared in the official Geometry Dash Discord server.
RobTop in his gym.
RobTop looking in a mirror, supposedly also in his gym.
While there may be more pictures of RobTop out there, we will only share known, publicly available photos that RobTop has shared himself.