I have been using Polar Beat now with a iPhone5 and Polar H7 HR monitor since a couple weeks. I also bought all in-app purchases.
I am a long time user of the S710i Polar watch and the T61 - coded HR monitor. I compared the Fitness Test results. Consistently I got 32 with the Polar Beat and 38 with the S710i. I made sure that the personal settings in both devices are the same and repeated the Fitness Test several times over within an hour. It is very strange that I got so different results. There is a big difference between a Fitness level of 32 and 38. That much of a difference should not be.
Otherwise I like Polar Beat. I think everything one needs to monitor is there and integration with Polar Flow is great. I very much wish for Recovery Status as an in-app purchase.
I only give 3 stars because of the Fitness Test issue.
Detlef Schmitt about Polar Beat: Running & Fitness, v1.5.2