It ain't. But a Mellotron inspired synth - that is a fair assesment of this new instrument for iPad from Omenie - who also make the Ellatron (without the HD - hence the iPhone version).
Essentially we have here a dual keyboard, five voice, sample based intrument with 27 preset sounds.
Presets:
MelloChoir
MelloBrass
MelloFlute
MelloString
EllaChoir
EllaBrass
EllaFlute
EllaStrings
EllaCello
EllaWoods
RiekoTron
RockOrgan
LeadOrgan
DeepViolet
CheezTastic
PopTabulous
EllaPulse
EllaBass
HardPlkBass
SquelchBass
AnalogSynth
PWMSynth
SaxyClavi
StellaPhone
StellaVibe
GlockenPing
Drums160bpm
These are all tweakable (slightly) with a tone control which is a sort of HP/LP filter afair.
Each keyboard can be transposed by a fifth - C to F giving a maximum playable range of 3 octaves.
Win
There's a cool little chord memory function which allows you to store up to 12 chords to be played back with the press of a button. This is actually a cool feature and gets around the inherent difficulty of playing anything meaningful on a small touch keyboard. You can then replay a set of chords with on hand on the buttons and play an additional line on the keyboard.
This is a useful feature for a quick jam or idea sketch too.
There are 16 chord memory setup locations which also store the assignment of the upper/lower sounds, octave, and tone settings.
Fail
Its not as snappy as playing a real keyboard, but it aint bad, so for tight staccato lines you may struggle to keep it in the pocket.
There is no master tune, so everything will need to be tuned to this instrument.
Overall
Not really any specific sounds I cant find elsewhere, but the chord memory feature is quite a useful one for jamming or throwing ideas down.