The "4K" output resolution is a true 3820x2160, though the quality of the video looks like dynamically upscaled 1080.The color depth is lacking, so there is some washout and slight oversaturation.
The Night Vision works well and the IR LED in the lens housing will illuminate a reasonably sized room. Use of the IR LED will drain battery rapidly (only 10 mins of recording @4k with night LED on). The IR LED cannot be used in tandem with the provided hood, as the hood blocks the lamp in the lens housing.
Framerate advertised at '30' FPS is an odd 27.94 instead of the expected 29.97. FPS@60 is true 60.0. Unlike other similar cameras I've seen on youtube, there are no noticeable stuttering artifacts in playback or lag in the framerate when the video transitions or pans rapidly.
Files seem to be split on duration, exactly 13 minutes both in 60 and 30 FPS, and not size. 13 mins at 60FPS = 1.77GB output file. Compression is mp4, there are no other options.
Complaints about inserting the SD card and battery are groundless, as a moment or two of fidgeting will reveal how they are inserted. The manual is brief but adequate as the functions of the camera are few and easy to navigate by either touchscreen or the buttons on the side.
The camera build feels pretty fragile and I'm sure any drop will destroy the unit.
The Microphone actually works well enough. Somewhat directional and wholly adequate for its purpose. All the +/-DB and lowpass cutoff functions of the Mic function as advertised. The output Audio track is Mono at 44kHz, even though the unit is supplied with a stereo cord. The mic is NOT powered by the 'hot'shoe, but by an internal battery. Hot shoe looks legit, but i havent tested it. The mic is connected to the camera by a minijack port on the left side of the camera, only accessible while the viewscreen dor is open.There is no headphone 'monitor' jack.
The digital zoom is a 'staged' zoom with 15 levels, not a smooth incremental zoom. There is no autofocus and subjects within a few feet will appear blurry. Anti-shake
I did not try the phone app, as it had negative reviews, and I'm hesitant to download unvetted software.
My product packaging did not contain any solicitation to leave positive reviews or stars, simply a card with a website for warranty registration. Website was only semi-functional as of 5/21
Sample video included is from camera, 4K@60fps using their mic set to 0dB and no filter.
**Edit** Amazon's compression really screws with the sample video i posted. It's not anywhere near as bad as it looks in the sample video.