Read information through bluetooth

I am doing an arduino project with a arduino UNO, DHT11 sensor, different MQ gas sensors and a HC-05 bluetooth shield. The idea is read the value of the sensors in a app created by me through AppInventor.
I read the value of the sensors in a "float" variable and send it by the function "BTSerial.print".
To read this in app inventor I use the procedure "Call BluetoothClient1.ReceiveTextNumberOfBytes" and what I get is that in the label where the information hav to be shown only appears a black diamond with a question mark inside.
Anyone know how I can solve this, or other way to read the informotion in appinventor through bluetooth?

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The unreadable characters in your text might be binary data.

You can decode them using blocks from the Web component

(no Web connection needed.)

See attached for how to use Web1.URIEncode to see the inner hex of text strings.

If you want more readable data, send them from Arduino using println() instead of write().

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