The ability to place international phone calls is a valuable skill in an age where the business world is increasingly global. While email is efficient for quick and casual communications, there is no replacement for the personal touch of a phone call. Unlike U.S. numbers, which have a standard format with a three-digit area code and seven-digit phone number, Japanese numbers have a variety of formats.

Skype is a free VoIP (voice over Internet Protocol) application for a number of operating systems and mobile platforms. Using Skype, you can make free or discounted phone calls all over the world with an Internet connection. If you're experiencing call quality issues while using Skype, you can make adjustments to improve your reception. In turn, you should have clearer audio, less lag and fewer drops while making Skype calls.

If you wish to call someone without using minutes on your iPhone's cellular plan, the Skype Voice Over IP (VoIP) application for the iPhone enables you to instant-message and call anyone who has a Skype account for free as well as call users who don't use Skype if you purchase a calling plan, according to the official Skype site. As of July 2010, the Skype application is available for free in the App Store on your 3G iPhone and can be used by accessing your phone's cellular network or a WiFi connection.