What you see here isn't a magic trick or illusion of any sort, the water droplets and later the beads actually are floating in the air. This phenomena is called "*Acoustic levitation*", where matter can be suspended in air (or any other sort of medium) via the use of acoustic radiation pressures from intense sound waves bombarding into the subjects at hand.
Intense sound waves do not have effects that are linear, that is to say the output of a system isn't directly proportional to the input into a system, ultimately making acoustic levitation possible. Some methods of the levitation can lift objects without making any sounds that the human ear can hear, and others do produce sound.
Essentially these subjects, the water droplets or beads or anything for that matter, are being bombarded with enough sound waves to cause them to not fall. One such way in which sound waves can be focused is by the use of a transducer (a surface that vibrates and makes the sound) and a reflector (a surface that reflects the already-made sound back towards the source).
The sound waves produced are longitudinal pressure waves, that move parallel to the direction they move along. These waves can bounce off other surfaces, following the law of reflections for sounds. The compressions of these waves sometimes meet rarefactions(reduction in the wave's density) and can combine to cause what is called a standing wave.
Standing waves seem to vibrate in place rather than flow from one place to another, giving an illusion of standing in place. With the right positioning of the transducer and reflector, and creating a sound wave that is parallel to gravity, the acoustic levitator creates a standing wave with some parts having a constant downward pressure, and other parts having constant upward pressure. This ensures that the subjects don't have a lot of pressure affecting them, ultimately causing them to levitate in a field of sound.
A longer, more detailed explanation of acoustic levitation here: http://science.howstuffworks.com/acoustic-levitation1.htm
YouTube video source for the gif: Acoustic levitation
YouTube video of acoustic levitation, and as well as manipulation of objects suspended in air: Three-Dimensional Mid-Air Acoustic Manipulation [Acoustic Levitation] (2013,2014-)
Real world usage for such a technique: http://www.anl.gov/articles/no-magic-show-real-world-levitation-inspire-better-pharmaceuticals
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