Freezing

Android

pywebview is designed to be built with buildozer. You need to include following lines in your buildozer.spec to bundle pywebview correctly

requirements = python3,kivy,pywebview
android.add_jars = <path_to_pywebview-android.jar>

pywebview-android.jar is shipped with pywebview and can be found under site-packages/pywebview/lib. To get its full path type

from webview import util
print(util.android_jar_path())

You can see a sample bulldozer.spec here

macOS

Use py2app. For a reference setup.py for py2app, look here.

Windows / Linux

Use pyinstaller. Pyinstaller picks all the dependencies found in pywebview, even if you don't use them. So for example if you have PyQt installed, but use EdgeChromium renderer on Windows, pyinstaller will bundle PyQT all the same. To prevent that you might want to add unwanted dependencies to excludes in your spec file.

nuitka can be used for freezing as well. You may want to use --nofollow-import-to to exclude unwanted dependencies.