https://codeweek.eu/docs/spain/guia-iniciacion-app-inventor.pdf
http://kio4.com/appinventor/9bluetootharduino.htm
http://kio4.com/appinventor/9Y_BT_servo.htm
http://www.mertarduino.com/multi-servo-motor-control-via-bluetooth-using-android-app-arduino-and-app-inventor/2018/11/22/
http://mitappsinventor.blogspot.com/2014/12/how-to-make-android-app-using-mit-app.html
http://webdegerman.blogspot.com/2016/07/control-de-servo-por-bluetooth.html
http://kio4.com/appinventor/9bluetootharduino.htm
http://kio4.com/appinventor/9Y_BT_servo.htm
http://www.mertarduino.com/multi-servo-motor-control-via-bluetooth-using-android-app-arduino-and-app-inventor/2018/11/22/
http://mitappsinventor.blogspot.com/2014/12/how-to-make-android-app-using-mit-app.html
http://webdegerman.blogspot.com/2016/07/control-de-servo-por-bluetooth.html