This Application buid on Android Studio The no 42 pin is coonnected to voltage sensor on IOIO-OTG board. You can purchase from http://www.amazon.in/Generic-FZ0430-Voltage-Sensor-Module/dp/B00NK4L97Q?tag=googinhydr18418-21&kpid=B00NK4L97Q&tag=googinkenshoo-21&ascsubtag=4b7ac183-8118-c808-8b23-00007c8a165b