This application note provides an overview of the demonstration firmware delivered with the STM32L-DISCOVERY evaluation board. It allows you to explore the rich set of power saving modes available in the STM32L microcontroller by using the STM32L-DISCOVERY embedded IDD measurement circuit that is used to demonstrate the real capabilities of the ultra low power microcontroller STM32L. The demonstration application does not require any additional hardware. Once the STM32L-DISCOVERY is powered-up through a USB cable connected to the host PC, the application is ready to display the STM32L power consumption of each low-power modes selected by the user. In addition the demonstration firmware allow you to explore touch sensing capabilities of STM32L microcontroller demonstrated by sensing of linear touch sensor or set of four touchkeys.