Summarize this article:

VoIP (voice over Internet protocol) applications allow you to make international phone calls at cheaper rates than through your phone provider. To make a VoIP call, you need a computer, tablet, or smart phone, plus an Internet connection.  If you call the USA often, check to see if your VoIP application offers subscriptions or monthly flat rates for a predetermined number of minutes; these subscriptions can significantly lower your per-minute VoIP costs. Many applications (eg., Whatsapp, Skype, and Facebook) allow users to place free calls within the applications — meaning that both you and the person you call would need to have the apps open on your respective devices. If your computer, tablet, or smart phone has a camera and an Internet connection, you may be able to video chat with your contact in the U.S. instead of calling them on the phone. Many social media sites and applications offer video chat for free. Some popular video chat applications include Google+ Hangouts and Skype. If you have limited Internet access but you have a landline with free local minutes, a calling card may be your best option. Calling cards vary greatly in rates — sometimes they seem cheap but have hidden fees.  Look for a calling card that offers easy-to-understand pricing and no additional fees. Popular calling cards include Pingo, EnjoyPrepaid, Comfi, Nobelcom, and CallingCards.  Note that calling cards are best for landlines and mobile phones with unlimited local minutes. Unless your mobile phone has unlimited local minutes, a calling card will not be the best option for you, as you’ll end up paying for the calling card minutes plus your mobile minutes. If you consistently make calls to the USA, ask your phone provider if they have any international calling plans or can offer you a discount. Calling collect reverses the charges so that the person you call pays for the call instead of you. Unless the person or company you’re calling has expressly told you it’s okay to call them collect, this is not advisable.  To call someone collect internationally, have the U.S. area code and 7-digit phone number ready, dial your international phone operator, and ask them to place the call for you. Phone numbers for international phone operators vary depending on which country you’re in; an online search of your country’s name plus the words “international phone operator” will reveal the number for yours. In the UK, you can call your international inland operator on 155; in Japan, you can call the international telephone operator at 0051.
Use an Internet-based application. Video chat instead. Purchase an international calling card. Consult your phone provider. Call collect.