3.5mm Headphone Jack
What about using durable materials, so we don't have to put special protection on our beautiful phones? Or about adding widely used features, instead of cutting them out?
In 2020 I'd like to see consumer friendly practices instead of stupid race for bigger numbers.
But I know it won't happen. Money rules, not common sense.
For those of us who can’t afford to buy a phone every year, 5G will be the most important feature.
Though I already have a 120hz smartphone. 2020 should be about cameras, both front and back; Although, In-display selfie camera is more important because this will lead to a real and unobtrusive bezelless screen (don't remove bottom bezel but make the side and top bezels as thin as the bottom).
2019 is not the Year of the 5G. 5G won't be real until Q2 2020.
Longer lasting batteries maybe