O, no doubt, Shattered Pixel Dungeon is a great example of GPL 3 in action. It’s a good, well balanced game without any kind of exploitative or predatory monetization. It’s the game that got me thinking about user rights, 4 year ago, because it’s such a stark contrast with all other mobile games: This is a game with respect for the user 
Try it on Flathub or Android for yourself. Be aware. It has taken hunderds of hours of my life.
As for the FLOSS element, In the section ‘license’ I want to make it pretty clear that ‘Java’ is an umbrella term and that OpenJDK is FLOSS, and that there are multiple vendors, some of them not FLOSS. I also intend to mention Java in containers or virtual machines, since a lot of modern software development focuses on that.
Credit were credit is due, I will mention Sun and Oracle when appropriate, but I’ll focus on the modern development experience first, highlighting how the GPL has created an ecosystem where different vendors are competing with each other for the best experience.