Up to now, when a user selected an output coordinate system, the coordinate system database that was used to take the coordinate system definition was https://epsg.io/
From now on, PIX4Dcloud and PIX4Dcloud Advanced will use an internal PIX4D coordinate system library that uses PROJ which is much more updated and also includes all of the coordinate system transformations.
Other PIX4D products are also using this internal database so that means that with this implementation, we will avoid inconsistencies between other products uploading data to PIX4Dcloud or PIX4Dcloud Advanced.
On another note, we also recommend visiting CRS Explorer - PROJ (developed by Javier Jiménez Shaw) which includes the list of the Coordinate Reference Systems included in PROJ and it could be a useful tool for everyone working with coordinates, searching for a coordinate system, or finding out what are the coordinate system used in the area of work.