I wanted a stand for my phone that is small, low profile and prints quickly but still able to support my phone in both landscape and portrait well and without being flimsy. After a couple of trials, this is what I ended up with. It's a tiny stand for your phone, no bigger than it has to be! It's only 35x24x19mm (LxWxH)!

The slot for the phone is angled at 15 degrees and it's 9.1mm wide. I use it for my Samsung Galaxy S8, which is 8.1mm thick. The extra margin is so that the phone can easily be put in or taken out of the slot. You can use this info and scale accordingly if you have a thicker phone.

It's small, prints really fast, takes up basically no space and is actually pretty stable. It supports your phone in both portrait and landscape (although you'll have to position your phone relatively center in landscape).

Print it standing up as you would when using it. No supports needed. I suggest you print it basically solid and with 0.2mm or smaller layer height. I did mine with 95% infill and at 0.08mm layer height, which took about an hour on an Ender 3 with 60mm/s print speed. At this scale, the degree of infill doesn't make much difference anyway.

Ender 3

No

No

0.08

95%