Hassanul_

Sorry I couldn't understand, had to use a translator. :)Anyways, are you using the same app as me? Have you set the settings as I have indicated above in the app? Also, check all the connections are correct (especially the TX RX wires to the bluetooth module). Check the jumper is set to serial mode. Alternatively, you can also try out the sweep/simpleexample example in the Arduino IDE examples to see if your motor turns correctly. If it does, it might be on the app side that is causing problemsLet me know if you need more helpCheers :)

Thats because you have to install the sabertooth library first before uploading. Try again and tell me if you still have problems. Cheers

Awesome! But connecting a relay directly to the arduino is generally a bad practise as the relay may produce voltage spikes as it is turning off due to e.m.f. The voltage spikes might damage your arduino pin in the long run You might want to put a diode in parallel to the relay.