RoboFail is a fantastic on rails shooting game for Android devices, that at first deceives you with simplicity, but quickly amps up the difficulty to keep you coming back for more. The actual game play is very simple, and involves simply touching (well tapping) the screen where you would like to shoot your projectile.
Your targets are a line of robots rolling off a conveyor belt. They are of varying colors and increase in speed as the levels increase in difficulty. The great part of this game is that you can't simply tap a robot in it's current location to register a hit - instead you have to predict where the robot will be by the time your projectile reaches the target area. If you are right you will be rewarded with a very satisfying crunch as a robot is obliterated into pieces.
This is where the physics of the game really shines. Not only are gravity and speed of the projectile launching impressive, but robots will literally smash into pieces, bounce off each other and hang precariously off the edge of the belt depending on how cleanly they are hit. There is real benefit in making sure that all the shrapnel of a robot is cleaned up (by shooting it off the belt), as shrapnel causes points to be lost.
To add to the difficulty, only 'good' robots are allowed to pass off the edge of the screen (the green ones), with the defective red robots requiring destruction before they leave the factory. Get it wrong and again, you will lose points. Finally, although you only start being equipped with a catapult, you can gradually upgrade your weaponry (and the strength of that weaponry) to include lasers and explosive mines.
The graphics and sound of RoboFail are top notch, and all over the presentation is close to perfect. Finally, there is plenty of content in RoboFail, so if you are after a physics based shooter with a twist, be sure to check it out.
In the words of the developer:
The game combines the laws of physics with classic shooting game action and is easy to get to grips with, but once you have got going it can be fiendishly difficult and keeps you coming back for more!