The device is not old, it has cutting edge mobile GPU. It's a Tegra 4. It has a fill rate of 2.68 Gpix/s (whatever that means, it's probably good :P)
Also it can run 2d games like Reaper at 60fps with many more sprites and effects and such.
Autorunner is just an utterly basic game, not being able to run that game at 60fps means either that C2 is not optimized, whatever graphics libraries are used are not optimized, or Autorunner is not made in C2 in an optimized way. You can't say that it's because the GPU is old because it's possibly one of the best mobile GPUs in existence and as a gamer who has many, many android games, so far C2 Autorunner is the only game that has given me fps noticeably below 60.
There is clearly a problem on someone's end, and it's not the GPU.
Edit:
Doing some probably incorrect math here but at 2.68 Gpix per sec / (2560 x 1600) resolution I can redraw the whole screen 655 times per second if fillrate means how quickly it can draw pixels. This means that I would have to redraw the screen 11 times every frame to drop below 60fps if this were just a fillrate issue. This probably isn't how it works, but however it works, I would imagine with that fillrate it would take a lot to drop to 30fps