I try to get the best solution running to use Android tablet and Ipad as external monitors.
Solution 1:
adb reverse tcp:5901 tcp:5901
vncserver -geometry 1200x1910 :1
run VNC and connect mouse via barrier/synergy is fast but you cannot use libreoffice on the second monitor
Solution 2
adb reverse tcp:5900 tcp:5900
adb shell monkey -p com.iiordanov.freebVNC -c android.intent.category.LAUNCHER 1
xrandr --newmode "1200x1920_60.00" 196.47 1200 1296 1424 1648 1920 1921 1924 1987 -HSync +Vsync
xrandr --addmode HDMI-A-0 1200x1920_60.00
xrandr --output HDMI-A-0 --mode 1200x1920_120.00 --left-of eDP
x11vnc -rfbauth ~/.vnc/passwd -nowf -nowcr -ncache_cr -clip 1200x1920-1920+0
is very laggy, but sometimes fast enough. This is apparently a x11vnc issue.
Solution 3 I am trying to find software for it instead of VNC into screen, use miracleCast or DLNA or other screencast Sofaware to a receiver.
How can I cast a virtual monitor, the command for activation of the the second monitor should be nearly the same to the second solution, just using miracast receiver App AirScreen instead of VNC
adb reverse tcp:5353 tcp:5353
adb shell monkey -p com.ionitech.airscreen -c android.intent.category.LAUNCHER 1
xrandr --newmode "1200x1920_60.00" 196.47 1200 1296 1424 1648 1920 1921 1924 1987 -HSync +Vsync
xrandr --addmode HDMI-A-0 1200x1920_60.00
xrandr --output HDMI-A-0 --mode 1200x1920_120.00 --left-of eDP
?????
The last one should be the command to cast the screen to the android device. either miracleCast or DLNA? Someone an idea?