The download button opens the iTunes App Store, where you
may continue the download process. You must have iTunes installed with an
active iTunes account in order to download and install the software. This
download may not be available in some countries.
From Virtual Switching Consultancy Limited:
VSC DialerThe VSC dialer supports IDD calls and calls to other VSC dialer phones. The VSC dialer will utilize WiFi if available and connected or can use the mobile phone service when there is no WiFi available. Compatible with iPhone 3G, 3GS, 4, 4S and iPad running iOS v4.0 or later Summary of FeaturesNo service subscription is required to make calls with the dialer to other VSC dialer phones Uses internal contact listProvides option to record conversation and playback on phone or send recording via emailRecent call listRegistered Status Network Quality IndicationEnglish, Traditional Chinese, or Simplified Chinese selected based on phone language