$6.99 version is well worth it.

I have sleep apnea. Just converted from CPAP to oral appliance and was adjusting it more, tighter, every night. Wife out of town so no one to report on my snoring. My first night with this app, recorded every snore. Again tightened the appliance the recommended amount and that night recorded. Result was a full night recording of just cat and dog noises, which it registers as sleep apnea noise. Checked and No snores. So now I use the oral appliance nightly, sleep better, and check the app for snoring. A detailed record and no snores. I would have paid $200 to get this test result. $6.99 is worth every penny. By the way, the alarm works in the background. It is a snap to review the record and see if it actually recorded snores which are quite evident on the display, and audibly, or just high ambient background noise. I love this app.

EUSJIM about SnoreLab : Record Your Snoring, v3.7.3