The PandwaRF Android application and its associated Gollum library are now available for 64-bit ABIs.
Honestly, we could have lived (at least a bit longer) with this lack of 64-bit support, since 32-bit support has always been present in almost all Android phones.
But Google decided that starting August 1, 2019, all apps using native code must also provide a 64-bit version in addition to the 32-bit version.
The deadline for migration is August 1, 2019 and this is a good thing as 64-bit code typically offers significantly better performance.
The supported ABIs are now: x86, armeabi-v7a, arm64-v8a and x86_64.