Depending on the performance of your equipment (computer/router/phone) StageWave has a latency between 10 and 20 milliseconds measured from the input of the mixer to the headphone output of the phone using USB 2.0 audio interfaces, which is low enough for a live presentation.
Latency can be even lower if lower latency audio interfaces like DANTE or Thunderbolt are used. Remember to visit our system requirements article.