Michael Fisher has an ongoing video series looking at smartphones of yesteryear and in the episode below he looks back at the Sony Ericsson P910, a device with no less than four user interface interaction methods! This was back in the days before Wifi, when Sony's MemoryStick formats were a thing, and when styluses (stylii?) were an everyday sight...

Although I too remember the UIQ phones very well, I have my own favourite - the original P800, which was the purer implementation of the concept by virtue of the flip being passive, i.e. with no wires. Meaning that, effectively, there were no moving parts to break, Psion style. In fairness, P900/P910 units ended up being reliable, so my worries were unfounded, but my heart still belongs to that first UIQ device, the P800.