So I had my first session using DM helper the other day. The initiative tracker worked like a charm, and my players and I also liked that it rolls for the health of the monsters rather than using the average amount. I found myself referring to the actual stat blocks in the monster manual/dnd beyond however rather than using the ones within the program. I'm not really sure why. I guess it was just easier for me to read in that format than the way the app presents it.
I ended up displaying maps that way I talked about in my other thread. I uploaded them under the "maps" section of the adventure, and then would manually reveal fog of war sections and hit the "publish" button to update it as my players moved through the dungeon. When required I would just use the manual zoom feature to size the grid to match my TV screen so that the players could put their minis on it. However 90% of the time that wasn't required and the grid was sized properly to begin with. (Which was a surprising coincidence)
I haven't started using the calendar feature yet to track the passage of time, however that is coming up in probably the next two sessions (when the party has to start paying rent every month lol)
The MVP feature for me right now is being able to publish photos of NPCs and monsters to the screen. It's one of those small things I never considered that makes a world of difference.