Rather than getting constructive feedback from the "internet", like you are asking, it would be much better to get constructive feedback from your actual potent

Rather than getting constructive feedback from the "internet", like you are asking, it would be much better to get constructive feedback from your actual potential users. So rather than posting to Show HN, Reddit, or random internet friends, make a list of 10 people who you could consider potential users and email them asking for feedback. Then for any/all that respond, given them a small reward from iTunes, Amazon, etc.