Still looking into this... Actually I'm measuring my 24/7 HR and HRV via Fluxtream Capture with a Polar H7. In addition to that I'm looking to get rid of the chest strap using soft gel electrodes so it doesn't interfere with my breathing and to get a more comfortable fit.
But what I see is that there's no way to get health, stress or any kind of medical utility from all this information in a way that, for example, the Firstbeat Bodyguard 2 that @Marco_Altini recommended does.
However it happens that Bodyguard 2 is not exactly of my liking because of it being an offline gadget, that's not connected to the smartphone and this way I cannot see live information and I depend on having access to a PC instead of streaming or uploading it directly.
So what I'm looking like is a way to get 24/7 HR and HRV information, via smartphone, with some health insights like, for example Polar Loop app or any of that kind does, and the ability to export all that information for more deeper research purposes.
So far, what I that majority of the products out in the market always fullfill everything except of one of this.
* Optical HRM wristbands like Fitbit and others are accurate for only HR but fail at excercising and HRV logging.
* Cheststraps, while being accurate, suffer from the imposibility to store data before syncing and are affected by possible connections lost, phone battery and depends on an app. I thought it could be addressed using an wristband that stores the info before syncing but they're not meant to be logging 24hours straight. However, in a way or another, using Fluxstream capture I had been able to store some of the information but lack of the software to analise it.
* Other, and more scientifical products address some of the above problems but suffer from the imposibility to see all this information online or in my mobile, they're stuck with old software and is difficult to move from one platform to another.
What I'm trying to get is any sort Fitbit Charge HR system, with the possibility to get the information to an open platform and with the accuracy of a chest strap.
What do you guys think about all this, what have you discovered with all the experience, what else can you add to this matter? I want to hear you!