I currently develop an application (Android) that uses some BLE devices to capture health data. I have a blood glucose meter which uses the ISO/IEEE 11073-10417 norm to communicate with the smartphone via BLE.
While other BLE devices work with 16byte hexadecimal strings that are sent from smartphone to device and back (using a CRC-checksum-byte at the end) the documentation of this IEEE standard doesn't provide me with information regarding this. If anyone had a suggestion how to start working on that I would be very thankful as I don't know how long it will take me to find out how this stuff works.