Comparing with TN LCD, STN LCD has a wider viewing cone and capable to show Graphic images.  And when STN LCD is built with a transflective polarizer or reflective polarizer,  it can work without a backlight which lowers the current consumption of the final device.  And Yeebo is capable to integrate the Touch- Key function by building the touch ITO layout In-Cell. It is a good solution to have a low-cost smart touch display.