Here’s an official demo of the organ patches in SampleTank for iPhone / iPod touch.
SampleTank is basically an app that turns an iOS device into a rompler synth.
SampleTank includes several different organ patches, including Hammond, Vox, Farfisa, church and pipe organs. Various drawbar organ instruments are included for blues, jazz, rock, pop, gospel, even hard rock and metal styles. Several pipe organ are also included from huge cathedral organs to more solemn soft church pipes.
IK’s DSP FX can add overdrive, chorus-vibrato, rotating speaker and reverb effects, also.
See the IK Multimedia site for SampleTank details.