It is the most popular, full-featured iPhone/iPad/iPod voice recorder available at the App store. There are lots of other voice recorders in the App Store but am in love with QuickVoice because of the multi-tasking feature.
The Multi-tasking support makes it easy for me to use other apps while still recording in the background. This makes it possible to use Quickvoice app as a call recorder. I use it alot in recording Skype calls on my iPad.
Ringtone recording is also possible with QuickVoice. You can produce your own custom ringtones easily using music recordings on your device, then assign different ringtones tones to different contacts.
Quickvoice recorder app for iPhone and iPad is free for download but there is a pro version which allows you to send up to 20MB of voice recordings via email. The free version offers the ability to send up to 5MB of voice emails.
If you purchase the QuickVoice Pro Recorder for your iPhone, you will get a free bonus copy of the award winning QuickVoice software for Mac and Windows PCs. The PC versions offer a full featured audio editor which makes it possible to use Quickvoice as a music production software.
NOTE: The iPhone version syncs its recordings with the computer version.
You can read about Quickvoice files transfer to computer process here and also check out how to convert Quickvoice recordings to mp3 files.
If you know alternative call recording apps, please let me know via comments.