Questions about Qt bluetooth notifications

[AndreaFurlani]

Hello everybody, I am developing a program to read some characteristics from a smart watch (heart rate, battery level, humidity and temperature).
To doing this, I am following the heart rate game example. From this example I am able to get notifications about heart rate from a simulator on my smartphone, but for the other parameters I am not able to get the values.
For example, for heart rate I'm doing this:

if (uuid == QBluetoothUuid(QBluetoothUuid::HeartRate)) {
            const QLowEnergyCharacteristic hrChar = m_service->characteristic(QBluetoothUuid(QBluetoothUuid::HeartRateMeasurement));
            m_notificationDesc = hrChar.descriptor(QBluetoothUuid::ClientCharacteristicConfiguration);
            m_service->writeDescriptor(m_notificationDesc, QByteArray::fromHex("0100"));

If i run my program, it finds the device and connect to it and I get correctly the new heart rate value everytime I push "notify" button on the simulator.

For the other services I don't have the equivalent of HeartRateMeasurment.
For the battery I tried to use BatteryService and then BatteryLevel as characteristic but my program does not read the values while standing still (but not blocked).
Which services and characteristics should I use to get the same result I get with heart rate?
Thank you very much for all the help.