Dolphin 16.12.3 and KDE Plasma 5.9.2 on openSUSE Tumbleweed. My iPhone 5 doesn't mount in Dolphin correctly. Every time I plug in the phone, it displays the "trust this device?" dialog, and I tell it to trust the computer. The phone shows up in Dolphin as a camera removable device (camera:/), which is correct. If I open it up in Dolphin, the only thing displayed inside that is a folder named "Apple iPhone 5 (PTP Mode) with two empty text files and an empty directory. None of the photos on the device show up. I had a similar problem in GNOME, but managed to work around it by mounting the phone in a slightly different way (remove the trailing ":3" from the gphoto URL), so I know it's not a problem with the device--just how it's handled. I can confirm that the device is trusting the computer, so there's some problem with how its contents are being mounted.
Not KDE. This was caused by https://github.com/gphoto/libgphoto2/issues/132