(Image credit: Future)

I've been tracking my sleep with the Oura Ring 5 for the past five months and love its comfortable fit and reliable data, whether I’m monitoring my 3 a.m. wake ups or how long I spend in deep sleep. However, the

Oura Ring 5, now from $399 at Amazon , does come at a premium price.

Keen to see if it was possible to replicate the accuracy of the Oura without the high cost, I started testing free sleep tracking apps — and discovered one that could hold its own against the best sleep tracker we’ve tested, the Oura Ring 5. The good news? It's completely free, with no hidden costs or trial sign-ups; all you need is a smart phone and a nightstand.

Here's how this free iPhone app compares to my $499 Oura Ring 5 (the gold costs more), plus how I'm using its tracking data to better understand my sleep. Looking for a wearable sleep tracker instead?…