I realize I'm reviving a somewhat old thread, but this is a consideration for me. I currently use vBulletin to host a community, and am considering NodeBB as a possible future replacement.
Many of the members of the community (myself included) use Tapatalk to access the forum. After seeing @luke's comment regarding NodeBB having a great mobile interface (thus making Tapatalk unnecessary) I decided to try it out in Chrome on my Galaxy Note 4. The experience was unpleasant.
As I tried to scroll through messages, the browser would sometimes go blank (solid white), then come back. As I was reading thread summaries, sometimes the metadata (age of the post, etc.) would disappear then reappear. I experienced those issues in the first couple minutes of testing. They were severe enough that I didn't want to continue to see if there were other more subtle issues.
Assuming the issues I saw (and any more subtle issues I didn't find) were all addressed, the fact remains that Tapatalk provides a single unified interface to a wide variety of forum software, and that is valuable to me. As proud as people may be of the usability and features of their particular forum software, there is value in providing a familiar user experience.
Tapatalk also provides a searchable registry of forums that allows users to discover new communities. Even if NodeBB has that, it would (I assume) be limited to other NodeBB communities. Tapatalk makes communities more discoverable.
I don't work for Tapatalk or have any affiliation with them except that I use the mobile app and run their vBulletin plugin. Tapatalk support is important to me as I consider switching to NodeBB.
I can appreciate if supporting Tapatalk doesn't make business sense for NodeBB at this point, but I believe it would be a mistake to dismiss the proposition.