I knew I'd be uncomfortable with a lot of it, but I also didn't realize how flat out bad I am at it. I've spent so much time fiddling with keywords, refreshing splash pages for app stores, making a good landing page, buying ads, adjusting paywalls, etc. But the uptake has been depressingly low. A few people downloaded the app, but not only have I had no paying customers and no reviews, no one has even tried the sync aspect of the app that I built a backend for! I really misjudged how little attention it would get in the app store, and how rapidly they'd bail from it.
My wife and I use the app. I find that code improvements bring some satisfaction even if there is no external ROI, whereas marketing type efforts are just a drag.