I dunno man. I sold a small company back in 2011 and it really was easier back then. Three out of four of our first leads tried to buy us because we were doing "real" machine learning. This was almost a pure API app. We didn't even have documentation we just told people we'd integrate it for them.

It is harder these days. Also, the product you mentioned "custom mobile app for housekeepers in rich families in the UK" I don't know how you're marketing that, but that seems like the hard part to me.

As for Twitter, people forget what it was like back when they were first starting. There were a ton of people you wanted to follow, but RSS couldn't handle the sheer numbers involved. Blogging had become so big and realistically you could only follow, say, 10 bloggers before being worn out with all the content. Twitter made it possible to get little nugget sized updates from thought leaders without having to eat the whole sandwich of some massive blogpost.