Recently I needed to receive an international call, from China specifically. I don't have a landline to receive free calls, so I set out to see whether my prepaid cell phone plan from Straight Talk or a free calling apps is capable of receiving free international calls. I searched the internet and read several forum threads but couldn't get a straight answer. There was much more information on placing a call, which almost always requires a fee. Ultimately, I used Google Hangouts to receive the call for free, and found out that Straight Talk should have worked as well. See more details and options for receiving free international calls below.
Receiving international call form China free on Google Hangouts
Having the call originate from China posed some unique problems, because many popular internet services from Google and Facebook are blocked there. So I knew a Google Hangout or Facebook video call wouldn't be an option. Skype and Apple's FaceTime appear to work, but aren't options for someone placing a call from a landline.
I use Google Hangouts with a Google Voice number to make and receive free VoIP calls in the US on my laptop and iPhone. (See this post for more info.) This ultimately ended up being what I used to receive the call. The sound quality was fine, but there was a delay of a few seconds and we were disconnected once over about 45 minutes. I haven't experienced this delay with domestic calls, but it wasn't too much of an issue. I would recommend this setup to anyone that needs to receive free international calls made to a phone number. Note, the user placing the call will be charged for the call.
Receiving international calls on cell phone
I also inquired with my cell phone provider, Straight Talk, about receiving international calls. Apparently this is a somewhat complicated question because we went back and forth about 5 times over email discussing the phone and plan I am using, where I got my SIM card, etc. Eventually I got the following response from Straight Talk customer service.
You should be able to receive International calls. Your plan will not be deducted for the service but the service provider of the phone calling you from China.
I didn't get to test this because Hangouts worked, but it's good to know that it 'should' be an option in the future. I suspect that many cell phone plans are similar and able to receive international calls for free, although you should probably check before trying because it will be quite expensive if not.