BIMx (for version15) is a free iPad/iPhone app but you will need to purchase a license to create the file from Archicad.
It will only allow you to see the model in 3D - not plans or elevations as such.
It was known as Virtual Building Explorer in previsous versions but VBE can not be saved to iPad/iPhone.
One of the forum moderators. Versions 6.5 to 27 Dell XPS- i7-6700 @ 3.4Ghz, 16GB ram, GeForce GTX 960 (2GB), Windows 10 Lenovo Thinkpad - i7-1270P 2.20 GHz, 32GB RAM, Nvidia T550, Windows 11