If you are using Go Direct Sensors, you need to use Graphical Analysis app for data collection.
If you are using Go Wireless Temperature, Go Wireless pH, Go Wireless Electrode Amplifier, Go Wireless Heart Rate, Go Wireless Exercise Heart Rate , or Go Wireless Link, the most likely cause is that your Android device does not have the location permission set correctly.
It is also possible that your Android device does not support connecting to devices that use Bluetooth low energy technology. To find out if your tablet or phone can be used with devices that use Bluetooth low energy technology, see Go Wireless Sensors - Computer, Tablet and Mobile Device Support Details.