Boosters are activated before you start exploring a location and make it easier to complete it. All in all, there are 3 boosters for searching for hidden objects (the Goggles of Epiphany, Compass, and Frozen Hourglass) and 3 boosters for each type of puzzle. Boosters are effective for a limited period of time.
Special tiles of the puzzles act as boosters. They appear in random places at the very beginning of the level.