I have followed the 15 videos of Brent Aureli on YouTube that explain how to code Flappy Bird on Android Studio. It also uses LibGDX, a cross-platform Game Development. Here is the link to the first video of his series: https://www.youtube.com/watch?v=rzBVTPaUUDg&list=PLZm85UZQLd2TPXpUJfDEdWTSgszionbJypackage I have written the code he gives on YouTube, and added the comments he makes.
Then, I added a score with a nice font in "PlayState.java" thanks to the following video: https://www.youtube.com/watch?v=xKqIx5XpxVw&list=PL07lH_mFGxLRn-W3XgsVrXOGp8IoRUf9c&index=13
I also added a highscore in "PlayState.java" to make the game more interesting. The way to add a highscore in explained here: https://stackoverflow.com/questions/46426899/libgdx-save-and-load-an-integer-for-highscore
Regarding the pictures, I found most of them online (tube, background, play button). However, I drew the bird with the website Pixilart.
Here is how it looks:
