I there, I have stopped for a looooong time “Applet” development but still continue on differents other technologies including Java.
I discover a year ago Titanium SDK, it is a cross-plateform SDK for Mobile development Android & IOS, It is sometime hard to find good informations about it and so I try to launch a forum, here its temporary URL Titanium SDK Cross-Plateform Mobile Development - Titanium SDK - Expert Forum (dzzd.net)
What interresting with this product is that you can extend it with pure Android Java extension (or pure IOS)
My OpengGL library for Titanium (mostly in Java) : GitHub - DzzD/TiGL: Titanium OpenGL : Android Graphical & Animation OpenGL Module
And a project demonstrating it capabilities : GitHub - DzzD/TiGLDemo: This is TIGL Demo repository, TIGL is an OpenGL Renderer for Titanium Mobile Application/
For more info , the new Titanium SDK official page since January 2022 is there https://tidev.io/