- "Did you think Super Meat Boy was a tad too easy? Then Space Is Key is the iPhone game for you."
- GameSpot UK
- "Fiendishly difficult but strangely captivating arcade experience"
- TouchArcade
- "Definitely a fun, challenging game"
- DailyAppShow
- "Space is Key oozes style from its simple mechanics"
- AppSpy
- "Is Space Is Key the most hardcore highscore iPhone game this year?"
- PocketGamer
- "Shining example of how effective keeping it simple can be"
- Altiapp