Personally I don't believe these. There is no doubt that phone radiation can heat things, like my thenar muscle. If I had time I would design a double blind placebo controlled study to test my hypothesis. I think this would be a good school science project. There is no evidence base for an opinion either way and if there was evidence (in the secret Apple archives) they would be crazy to release it. Meantime, I'll keep an eye on this subject - maybe with a Google Alerts search as shown in this link which searches for "hand pain from radiation of iPhone".
The lesson from this is that plenty of content on the internet is useless, or just plain wrong. This might include my comments here!