BLE Android - onConnectionStateChange not being called

If someone is having a similar issue, the problem was finally solved by changing the BLE chip used by the peripheral (arduino). Before that change, a workaround I found was turning off and on the BLE after each connection. The solution was not perfect, but improved the connection rate a lot.

I am not sure if you're still looking for an answer for this question. Personally, I would not advise making "fast and short connections triggered by user action" for low energy devices. Instead you could set the autoConnect option to "true" in your connectGatt method.

device.connectGatt(mContext, true, mGattCallback); [instead of false]

Hope it helps!

Android Bluetooth needs to be recycled occasionally, have you tried restarting the BLE on the device when you encounter this timeount?

Here's a snippet I've used to restart the BLE when strange things start happening.

static Handler mHandler = new Handler();
public static void restartBle() {
    final BluetoothManager mgr = (BluetoothManager) ApplicationBase.getAppContext().getSystemService(Context.BLUETOOTH_SERVICE);
    final BluetoothAdapter adp = mgr.getAdapter();
    if (null != adp) {
        if (adp.isEnabled()) {
            adp.disable();

            // TODO: display some kind of UI about restarting BLE
            mHandler.postDelayed(new Runnable() {
                @Override
                public void run() {
                    if (!adp.isEnabled()) {
                        adp.enable();
                    } else {
                        mHandler.postDelayed(this, 2500);
                    }
                }
            }, 2500);
        }
    }
}