Smartphones have already hit Full HD 1080 x 1920 resolution displays, but they're not stopping at that. Even if you can't see the difference anymore.

An internal slide from Chinese company Vivo has shown what its next Vivo Xplay 3S smartphone screen looks like in comparison to other models. The 5.7-inch screen manages to cram in 515ppi at a 1440 x 2560 resolution which, as you can see, makes the iPhone's 326ppi Retina display look pretty blocky.

While we're all for progress, haven't we reached the point where human eyes can't even tell the difference? It doesn't seem so, according to Vivo. So what's next - 4K mobile displays before UHD TVs even make it into many lounges? At least that would push content provides to create more in 4K.

The 1440p screen should be arriving next year at some point. And with LG reportedly also working on that resolution, the only question, who gets there first?