Levitating is a skill taught in Exillium which, with applied concentration, can levitate one high off of the ground. Sophie and her friends learned the skill while attending Exillium in Neverseen. In Nightfall, Keefe, Linh, and Sophie use it to levitate to the top of the dome in Atlantis. Fitz used it in Flashback to drop Sophie so that she can teleport when needed. Tam and Timkin Heks are said to have very good levitating skills, because they attended Exillium.
Levitation is a part of using elvin crutches, as shown in Flashback when Fitz breaks his leg.