Co-founder here - thanks for the great feedback Osmium. You're quite right in that the number of people who have unilateral hearing loss is pretty high (it's close to 40% from some recent studies).

We're working on developing a test that works well for people with single ear hearing loss for a future app update - would you be interested in trying out our beta? Please drop me an email if you are: varun [at] soundfocus [dot] com.