This is probably one of the first reviews I have ever written. You would find a lot of content about gadgets in youtube (with so many tech channels these days) but the only problem I have with that is I can not skim-through the video content just to see if there anything relevant that I need to know. I need to see/hear the full specifications and comparison what the video has to say. With this post (and possibly a series of posts with other gadgets that I own ) I am trying to have some notes that are usually not in the Amazon listing or manual or any overall review videos.

Yi 4K Action Camera one of the affordable action camera. Following are the observation.
  • The build quality is really good and quite compact.
  • The time lapse works great, here is a sample. This is the most detailed version i.e. one frame per 0.5 seconds. For slow moving scenes like the cloud or sea, one can use even slower settings like one frame per 10 seconds and beyond.
  • I also tested for the other extreme - slow motion. It highest setting that it has is 8x slower and I compared the slo-mo of a fast moving ceiling fan shot by this action camera and POCO phone F1, video from this one looked better.

  • It has a really wide angle field of view which sets action cameras apart from the mobile cameras.
I am happy with most of the things with the camera, except
  • The wifi works for AP mode where you can connect your phone to the camera via wifi bit the station mode does not work. Neither I could get any documentation what is it supposed to do.
  • You may have to spend extra on accessories like waterproof cover, tripod, remote etc. (The voice action vacation is cool tough if you don't want to use a remote.)
Update -

I thought it's worth mentioning the following couple of tools which I found out while creating this post.

1 - Online video editor -  I could crop and resize videos using

2. Using FFmpeg I could stitch the slo-mo videos in command line itself to show them side by side. Thanks to StackExchange.

ffmpeg \
-i input1.mp4 \
-i input2.mp4 \
-filter_complex '[0:v]pad=iw*2:ih[int];[int][1:v]overlay=W/2:0[vid]' \
-map [vid] \
-c:v libx264 \
-crf 23 \
-preset veryfast \