- Increasing price. Yes, it started at only $10/year, and I've gradually increased it as the product has improved. It's very difficult to know the optimal price. I use split testing for some things but it feels wrong to do this for price, and with current conversion rate it would take ages to get meaningful results anyway. I'm hesitant to push price too high because lowering it back down would be tricky. Existing users paying a higher price would be annoyed. Also, at this stage I think increasing the user base would be more valuable long term compared to milking the current users for more money. I've been wondering if I could add a higher priced tier in future for more advanced features.
- Yes! I definitely want to recommend texts to people based not only on difficulty, but also on interest. This is something that will become more valuable with more users and a larger, higher quality library of texts. It isn't highest priority right now, but hopefully in future.
- Yes. I developed some features to target at teachers managing a class of students: http://blog.readlang.com/2014/02/12/readlang-for-teachers.ht.... I got a bunch of teachers using it with real classes but decided to abandon the idea because: 1. The response was positive but usage wasn't what I'd hoped. 2. Focus. As one guy I've got enough on my plate making an awesome product for self motivated individuals. Diluting my focus and the focus of the product seems like a very bad idea.