I'm using Pillow (without subscription) I like it's widget design and overall design - £12.99 for 3 months! £51.96 a Year - Nope! - although it does offer power naps via subscription only.
I've also got AutoSleep but it's a bit overboard with squeezing so much info into it's design and doesn't offer power naps.
Is there anything that offers this feature that's either free or a reasonable one time purchase.