Downloaded on a nexus 4. Played with touchscreen and with a moga pro. Runs at 30 fps with drops. Has the original uncut versions of the songs, so it's not exactly the same as the Dreamcast version. As a side effect of that, the game rarely starts out with that one Offspring song.
Touchscreen controls are ass. The game auto accelerates the car while in drive and breaking is handled while in reverse. This makes hard stopping and boosting pretty hard to control effectively.
Gamepad controls with the moga pro are butt. The layout mimics the Dreamcast version but have a flaw: gas and brake are mapped to the bumpers with no way to change them to the triggers. That means no analog braking or acceleration. Feels like steering is digital as well. The timing for crazy boosting is seemingly off and inconsistent as well. Even with those problems, playing with a controller is a billion times better than with just the touchscreen.
It's cool that they gave the game away for free and it's definitely Crazy Taxi. I'm still somewhat disappointed that it was so close to being a perfect port. As it is, it's serviceable.