[dsr_]

Phone mechanisms which worked for me:

- the original Motorola StarTac "Star Trek Communicator" flip.

- the Danger Hiptop / Sidekick II rotating screen-over-keyboard

- the Motorola Droid slide-out keyboard

- the OnePlus 7Pro slide-out selfie-cam

Only that last one was motorized, but mine is still working. Holes and divots and islands and any other kind of screen interference is strictly inferior.

[wolvoleo]

I liked the slide down mechanism of the nokia 7110 also. Bonus points for the microphone being at the bottom of it so it served a purpose by putting the mic really close to the mouth (unlike later sliders like the banana phone which didn't do this)

[mschild]

I loved the Xiaomi Mi Mix 3 slide mechanism.

The front camera was hidden and you would slide the back up to expose it. Was not motorized and functioned using magnets. Very similar to what old dumb phones used. Super reliable and easy to use.

[euthymiclabs]

The slide out cam on the One Plus 7 Pro was exceptional. I still miss it sometimes.

[ninju]

I had that phone and it was a great phone with the percentage screen real estate.

Bummer that AT&T dropped network support for it just a year after I got it

[s0rce]

I liked the Startac and Razr formfactor.