Some of his most popular tunes include Commando, Monty on the Run, Sanxion, International Karate, Skate or Die!, Crazy Comets, Master of Magic, Delta, Thrust, Lightforce, Spellbound, One Man and his Droid.

[6] His least favourite was Samantha Fox Strip Poker, which he admitted to having done purely for money; he was listed in the game credits with the alias John York.

[3] He has stated that he had many musical influences including Jean Michel Jarre, Larry Fast and other synth bands.

Playback of samples was facilitated by exploiting a feature in the SID sound-synthesizer chip: altering the volume register produces an audible click, and altering the register thousands of times per second enables a relatively crude (but surprisingly clear and sophisticated for eight-bit computers) form of sample playback.

After the Commodore 64 period, he wrote some soundtracks for games which appeared on the Amiga, Atari ST, IBM PC and Mega Drive.

Hubbard has also performed his old music on piano with the support of violinist and fellow chiptune composer Mark Knight.

In November 2016, Hubbard received an honorary degree from Abertay University for his contributions to video-game music in the 1980s.