Are Aggregate Format Descriptors supported?

[mundodisco8]

Is your feature request related to a problem? Please describe.
I'm exposing the Battery Health Status characteristic of the BLE Battery Service (section 3.6 here Its data is an struct (see 3.26 on the GATT Spec Suplement)

I added 5 Char Presentation Format descriptors, one for each item (hopefully correctly configured)

And tied them all up with my aggregate format descriptor (Part G Generic Attribute Profile, section 3.3.3.6). When I read the data, though, I just get 15, which is the value of the first field, flags, correctly presented as a uint8_t without units (as described by its format descriptor).

It's the first time I do this, and I'm using an ST microcontroller (I opened a case on their side too, to make sure I did everything correclty) but I wanted to know if aggregate descriptors are supported in the Android App (or the iOS App, for that matter)

Describe the solution you'd like
To use Aggregate Format Descriptors, so I can define presentation values for characteristics that present a range of aggregated data.

Describe alternatives you've considered
I could create individual characteristics for each char, and give them format descriptors, but I think that given that I'm using a Bluetooth defined char, it would be nice to get it correctly set up.

[philips77]

Hello,
Thank you for creating the issue. Full support of Characteristic Presentation Format and Characteristic Aggregate Format descriptors is tricky. In theory, the CAF descriptors can point to CPF descriptors of another characteristic. This, however, is difficult to parse using Android or iOS API, where the handle numbers are not available.
We could just use the CPF descriptors belonging to a characteristic to parse its value. Currently we're only reading first found CPF descriptor.

I'll create a task for this to nRF Connect.

[mundodisco8]

Thanks for taking it into consideration. Some of my colleagues at work use iOS and could benefit of it if it's feasible and ends up being implemented, should I create a ticket on the iOS repo too?