Mobile

IntPtr deviceContext = GetDC(IntPtr.Zero);
            
            Rectangle rectangle = Screen.PrimaryScreen.Bounds;
            using (Bitmap capture = new Bitmap(rectangle.Width, rectangle.Height))
            //Get screen context
            using (Graphics deviceGraphics = Graphics.FromHdc(deviceContext))
            //Get graphics from bitmap
            using (Graphics captureGraphics = Graphics.FromImage(capture))
            {
                // Blit the image data
                BitBlt(captureGraphics.GetHdc(), 0, 0,
                    rectangle.Width, rectangle.Height, deviceGraphics.GetHdc(),
                    rectangle.Left, rectangle.Top, SRCCOPY);
                          
                
                deviceGraphics.DrawString("Hello", Font, new SolidBrush(Color.Black), 10, 10);                
            }
            // Doesn't work: InvalidateRect(deviceContext, IntPtr.Zero, true);
            //Doesn't work: RedrawWindow(deviceContext, IntPtr.Zero, IntPtr.Zero, RDW_ERASE | RDW_INTERNALPAINT | RDW_UPDATENOW | RDW_INVALIDATE);
            // Doesn't work: SendMessage(deviceContext, WM_PAINT, 0, 0);

            // I tried RedrawWindow with all possibile combinations of all parameters (RDW_XXXX)!
            // I also tried to add directly IntPtr.Zero as Handle parameter
            // In all cases the text "Hello" is still drawn until I click on the start button
            // I run the code on WM 6.1.4 Professional (Emulator)