facebook pixel uses https protocol, which b4a handles
quite easily.
in practice, facebook pixel is javascript meant to run in
a web browser. technically, that javascript could run in
a webview, which b4a handles quite easily.
facebook provides a javascript code snippet for you to
insert in your javascript-enabled webview. that snippet
downloads yet more javascript from facebook. that code
may or may not run in a webview.
you obtain the initial javascript code snippet from facebook
by filling out a form.
the only way the code would run is in a javascript engine,
ie, a browser or webview. it's some unclear what you would
do with facebook pixel in a b4a app, but, technically, it
could work. because of webview's limitations, you won't
know for sure until you try. get the initial code snippet from
facebook, do up a little webpage and load it into a webview.