+Screencastify is celebrating the 4th by bringing us video annotation and a spotlight.
After you begin a screencast, Alt F to begin the spotlight. Left and righ and up and down arrows allow to to increase / decrease to spotlight.
You should see a small toolbox which allows you to select a pen for video annotation. After I mentioned lack of touch screen support, an update was available the next morning. To make things easier you can cycle through pen color with the left and right arrow keys.
Great job Screencastify on these new features.