Great Sound App
UPDATE - November 2018:
Some users have reported issues with the iOS version of the app crashing repeatedly after installation. This has not affected all iOS users, but I know it is a problem for many. It's been a challenging problem to solve and we are working on the updates now.
Please check this page again soon for more updates, or sign up on the email list to get updates as soon as the new app version is released.
Thanks for your patience and support!