The INNOCN PU15-PRE is a feature-packed 15.6-inch portable monitor built around an excellent 4K OLED touchscreen panel. First and foremost, it impresses with its picture quality. Thanks to an exceptionally high pixel density at 282 PPI, the picture is superbly sharp, and aspects like color vibrance and black levels are very pleasing to the eye, as you would expect from an OLED panel. On top of all that, it has excellent color and brightness uniformity, almost no notable contrast deviation, and more than enough brightness to be used in bright rooms. I would only somewhat hesitate to take it out in the open, as in that case, its glossy panel surface can and will cause issues with reflections. The panel responds well to calibration, in doing so you can get its color accuracy to a level where you can use it for serious video and photo editing, digital design, and everything in between.

The glossiness of the panel is partially present because of the fact that the panel has a smooth glass surface in front of it, which is there to reduce friction when sliding fingers or passive stylus pens across the panel. The touchscreen functionality doesn't feel like it was slapped on just to get an extra feature on the list; the touchscreen is satisfyingly responsive, and it does a solid job with palm rejection. I'm no digital artist, but I can certainly imagine such a crowd using the INNOCN PU15-PRE to make sketches and quick drawings.

Another welcome aspect of the INNOCN PU15-PRE is its integrated battery, which can keep it alive for up to four hours (depending on brightness) without an external power source. This will make your life much easier when you want to get some work done in a place where there's no power outlet in sight or when dealing with a power brick isn't practical; for example, when holding a quick field presentation for a potential client.

Despite its 5,000 mAh integrated battery, the INNOCN PU15-PRE remains thin and sleek. With a metal case and glass front, it looks like a serious, high-end portable monitor. The aesthetics are diminished by the supplied 2-in-1 protective case, which doubles as a monitor stand. The case looks and feels like it comes from a monitor costing a fraction of the PU15-PRE's price. It's not great in terms of ergonomics either, as it can only support the monitor at one or two tilt angles, but it does protect its front, back, and sides when carried around, so at least there's that.

There are some other issues with the PU15-PRE, such as a lack of gamma controls, which makes it impossible to fix the gamma-related issues, resulting in crushed shadow detail, without proper hardware calibration of the panel. It also has a high input lag, making the monitor a poor choice for any kind of more serious gaming (think multiplayer shooters).

The biggest deterrent is the $780 price tag, which makes the INNOCN PU15-PRE a reasonable choice only for those who plan to use their portable monitor daily, who need features like the touchscreen and integrated battery. If you recognize yourself in that description, you'll be hard-pressed to find a portable monitor that offers a better experience than this one.