The hardest flappy bird version -> The Hardest Unhappy Bird.
Yes, it is harder than flappy bird as you have to flap two birds at one time.
Are you ready to challenge yourself?
https://play.google.com/store/apps/details?id=com.boost.games.thehardestunhappybird&hl=en
Highest "Flappy Bird" Score
The hardest flappy bird version -> The Hardest Unhappy Bird. Yes, it is harder than flappy bird as you have to flap two birds at one time. Are you ready to challenge yourself? https://play.google.com/store/apps/details?id=com.boost.games.thehardestunhappybird&hl=en