I was searching the forum on compatibility of the Samsung Galaxy Note 5 with Tello and found a thread back in 2018 about frame skipping. Tried using the WIFI extender and the skip still happen. However, a helpful tip on youtube video (can't seem to locate the link for some reason) on reducing frame skip by running the Tello app first before connecting the drone to phone's WIFI and it worked on my old Note 5!

For anyone else who are interested, the same method works for Note 10 and Note 10 plus as well (yep, before this, my Note 10 plus was experiencing frame skipping too).

Hope this helps.

Nice Tello tip.