Sending data from an arduino to an app via bluetooth

Hello i am new at app making and i am making an automatic water can with arduino.I want to make an app that i can see the humidity but i cant receive data can someone help.

There are many examples in this community, look for information about Bluetooth.

Post your .ino file, and your Downloaded Blocks Image here.
Also show the attributes of your BlueTooth Client and your Clock component.