System requirements

PC, Mac or a mobile phone with a working web camera.
Google Chrome, version 53.x or higher.

Internet connection (minimum requirements)
Users: 0.5 Mbit/s upload, 1 Mbit/s download
Trainers: 1 Mbit/s upload, 4 Mbit/s download
TCP port 443 must be opened for all kinds of traffic.

Internet connection (recommended)
Users: 1 Mbit/s upload, 4 Mbit/s download
Trainers: 2 Mbit/s upload, 4Mbit/s download
In addition to minimum requirement, UDP port 3478 opened.
For the best experience, UDP ports in the range 1025-65535 should be opened.

Note: stable link with upload and download of at least 350kbit/s each is mandatory. Users with unstable links with lot of packet drops might have audio/video freezeings and delays.