Usually what I can think is an info product. A small app can work too. I build hnanalytics.sawirstudio.com might be the example of small app from my mind.
I built some info products, but it doesnt really produce anything. Which is why I say probably because of me have almost no followers or the products indeed didnt have the market
I'm guessing you don't have enough data to make any determination. Perhaps look at how competitive the space is for your apps and see if there is a market out there that you don't know about?
You can say that. Did you mean data as in...statistic of the market? If you don't mind where do you usually go for that data?
You can use Google Adwords and do a search on the keywords for your product and see the keyword volume and avg bid price. That will tell you roughly there is someone searching for what you are selling.
That's a possibility. Thank you for sharing @ApolloRising