Using GOFAR in a typical car, SUV or 4*4 etc doesn't impact your car's warranty.
GOFAR strictly adheres to the "OBD2 protocol". This protocol (it stands for On Board Diagnostics) makes car emissions testing possible and governments around the world have legally mandated that car companies comply with this protocol and install it in their cars as part of pollution reduction initiatives.
It's been a legal requirement in the US since 1996, in Europe since 2001 and in Australia since 2006 for example.
Car companies are not allowed to use anti-competitive measures to "lock" the use of this port to their own dealers or mechanics and plugging an OBD device into a car's OBD port will not affect the car warranty as long as that device is not changing the car's factory designed conditions.
Some devices may affect your warranty if they change a car's settings. For example, some devices actively seek to change the factory designed parameters of a car (such as increasing fuel flow speed or boosting oxygen intake or fuel burn pressures) in order to get more performance or power from a car. In that situation, manufacturers could reasonably claim that this may void a warranty. Rest assured though that GOFAR does NOT in any way do this. We do NOT change any of the car's factory designed parameters. We are NOT an engine tuning solution (and we generate improved fuel economy purely by helping the driver adjust their driving style).
In fact, GOFAR, is used by insurance companies to measure their drivers and manage and reduce the risks of driving. Insurance companies are not known for taking risks with warranties and they know that the OBD2 protocol is a government mandated system with which car companies must comply.
Ultimately any decisions about the validity of your warranty are between you and the manufacturer, but given the information above, and the fact that we're unaware of any manufacturer withdrawing warranty cover because of a compliant OBD device like GOFAR we hope this helps explain why we say GOFAR does not impact your warranty.