In panel-mounted IFR GPS, Class A airspace is not systematically depicted on moving maps and airspace alerting is not systematically provided.
The databases used for navigation and mapping in these units use the ARINC 424 standard, and I think that does not allow for Class A coding. I think there's a historical reason for this - remember there is no Class A at levels below FL180 in the USA, and there is little to map, since it's all Class A up to F600.
Some UK Class A is mapped where it is a TMA, because you can code TMAs, but no Class A airways are mapped as airspace (only route lines).
Sorry for the following use of capitals: YOU ABSOLUTELY MUST NOT DEPEND ON ALERTS FROM A GPS FOR CONTROLLED AIRSPACE AVOIDANCE. I don't know about the various handheld gadgets and software.