You have no idea what you’re doing and you are blindly digging yourself deeper into the hole by writing more apps. I wrote a couple of quality apps and I had seen some success financial success with them, you are not moving in the right direction.

You can’t write an app and think up a marketing plan afterwards as an extension, it’s the other way around - you find an audience with a need you can satisfy and a loudspeaker to reach them about it, only then you add an app as an extension to that.

If you want to write quality apps as a hobby then go for it, but don’t expect financial stability from that or you will face emotional ruin on the heals of financial struggle. Just don’t.

If you’re looking to make a living then go be a consultant to small-medium businesses. Fire bad clients asap, make unexpected treats for good clients. Repeat business accumulated over a few years will set you up for life.

Virtually no businesses work like this. Maybe NY Eve wasn't the best date, and it's great if you get a boost from the announcement, but you need to follow up with marketing, continue talking to customers, sales, calling people, etc. Most users will not hear about your business from the initial announcement.

A lot of times when you see a business take off after an announcement, it's because they worked for months prior to build an audience. Sometimes that's the developers audience (if you have a lot of twitter/blog/etc followers), or it can be because you preannounced it, collected emails, and kept them engaged as it was being developed. You still need a game plan for after the announcement though.

Good luck... try not to get discouraged if it's not an immediate success. (Your other point, about it being too niche, can be a problem if that niche isn't valuable enough.)