@scottk, I moved your question about the AudioCardio https://audiocardio.com/ app for tinnitus and hearing to this discussion about best apps for hearing loss to connect you with other members trying out apps.

it looks like AudioCardio offers a free trial period before you would have to commit to paying for it. But the trial is only 14 days long. I'm not sure you would see significant differences in that short time period. I'd be interested to get your review should you decide to trial it.