(Updated Feb 2023)

Here's how I'm building CrossWords for Android.

First, cd into the directory xwords4/android. Everything
happens there.

To build and install the debug version of CrossDbg (a variant meant
for development that can co-exist with CrossWords):

# ./gradlew clean insXw4dDeb

(The clean target can be omitted if you're not switching branches,
adding to strings.xml, or making API changes that require that
everything be recompiled)

To make a release build:
# ./scripts/arelease-clone.sh

You'll get prompted to re-run with the --variant flag that will tell
which version to build.  There are currently three release variants

* Xw4Foss: shipped through GitHub, SourceForge and the author's
  website, this variant does everything, including (potentially but
  not now) using libraries the F-Droid communitity doesn't trust, and
  supporting features that Google no longer wants third-party
  developers to use (e.g. sending and receiving SMS messages, if the
  user so chooses.)

* Xw4fdroid: This variant follows the F-droid community requirements
  to avoid unfree libraries (like Google Pay, which I used to use for
  the offline Push feature).

* Xw4GPlay: This variant omits features that Google no longer wants
  third party apps to include, such as play-over-SMS and updating from
  third party sites.


I do all development on Debian and Ubuntu Linux systems. I have built
on MacOS (prior to 2017), where once you got all the necessary tools
installed via homebrew there was only one problem I'm aware of: the
parameter 'white' that's passed to convert by
android/scripts/images.mk on Linux systems needs to be 'black' on
MacOS. I have no clue why. If you don't make this change the subset of
actionbar icons that are generated from .svg files will be
black-on-black.