Follow along with the video below to see how to install our site as a web app on your home screen.
Note: This feature may not be available in some browsers.
And if you want to know how to add a checkbox to a grid, see this article:
You can do multiple selection in a listbox (not a combo box) simply by setting the MultiSelect property to .T. To make a multiple selection, users holds down Shift and/or Ctrl keys while clicking on an item. To find which items they have selected, you use the Selected property.