The "Download Now" link directs you to the iTunes App Store, where you must continue the download process. You must have iTunes installed in order to open the link, and you must have an active iTunes account to download the application. This download may not be available in some countries.
From Dominic Rodemer:
iSynth is a virtual monophonic analog-synthesizer for your iPad. iSynth is designed and optimized for live performances.Features At A Glance: Dual Oscillator:- Generating square, triangle, saw tooth and reverse saw tooth waves.- Octave selector- Lag processor- Cross-Fader- Oscillator fine-tuning- Oscillator synchronization LFO Filter:- Supporting square, triangle, saw tooth and reverse saw tooth waves.- Filter, vibrato and tremolo modulation ADSR Volume Envelope Generator:- Control attack, decay, sustain and release ADSR Filter Envelope Generator:- Control attack, decay, sustain and release Low Pass Filter:- Frequency cutoff from 10 kHz Arpeggio Modul:- Up to five notes- Select between up, down, up/down and random playing Keyboard:- Switch between 4 octaves Patches:- Shiped with default patches- Save unlimited user defined patches- Share your patches with others via iTunes filesharing AirPlay:- Stream directly from iSynth to any AirPlay compatible device