A toy phone I designed for my kids. The buttons need a piece of foam rubber below before gluing the button plate on top. I figured this to be simpler and more durable solution than using some kind of printed spring mechanism in this size (I tried a few versions and failed miserably). I guess TPU could probably be used for a version of the buttons to obviate the foam, but I didn't have that available.

The "screen" is an Instax mini photo and can be changed. The front plate on top of the photo slides in place from the top and is held in place with one M3 screw (6 mm long). This is to prevent a toddler taking it out and eating/destroying it like they tend to do. There is a 5 mm deep hole in the back piece for a 4 mm long threaded insert for that screw.

I used PLA(+, Elegoo), 0.4 mm line width and 0.2 mm layer height. No supports needed or even brims for other than maybe the buttons (at least on PEI). The tolerances ended up being pretty loose so success should be easy on any printer. The buttons are all in one file but the rest are separated so it's easy to print those in different colors if you wish.

PS. I don't know how that gap between the screen and buttons became so wide, there actually was zero tolerance between those pieces in the model...