Worth it so far...
I have an Apple Watch Series 1 that I use for heart rate monitoring in Zwift. My watch is stuck at WatchOS 6.3 and Zwift stopped supporting it in late 2022. I switched to the free HeartCast app and that worked OK but was glitchy and had many brief dropouts. With the last iPhone update to OS 17.3.1, HeartCast disappeared from my watch and according to the App Store, BlueHeart was the only app still supporting my watch. With the free version, the ad would not display so the app wouldn't work. I paid for the Pro version in hopes that it would work and it worked perfectly - connecting immediately and no dropouts during my Zwift ride 👍 I took off one star for the ad-supported version not working and will update later if I have any issues.