Ambrosia Software has introduced iToner 1.0.0, a utility that enables iPhone users to place custom ringtones onto the device.

The Mac OS X solution enables an iPhone owner to transfer any MP3 or AAC audio file to their Apple mobile phone. The utility is being made available as for free download as a trial version here.

iToner lets users transfer new ringtones to their device using drag-&-drop. Once a ringtone is synced with the iPhone a user can switch them on (or off) at will.

iPhone allows users to assign different ringtones for different contacts. iToner can extend this beyond Apple's pre-supplied ringtone collection.

iToner costs $15, requires Mac OS X 10.4.10 or later, and is a Universal Binary application for both PowerPC and Intel-based Macs.