Cool twist on Flappy Bird! And just as difficult too.
A point I'd like to bring up is that it felt kinda unfair that the bird could just kill itself on the pillar that it just passed through, since I lose control of the pillar after the bird passes through it.
Although I only noticed after switching on Easy Mode, I think that the pillar positions aren't varied enough. The gap of the pillars would always spawn very close to the middle of the screen, so if Easy Mode was toggled on when the bird was at the middle of the screen, the game would basically play itself.