Regarding the iPhone 5c, the attack from Sergei Skorobogatov is very interesting.
"The bumpy road towards iPhone 5c NAND mirroring" - https://arxiv.org/abs/1609.04327
And the video:
A note -- if you're linking to arXiv, it's better to link to the abstract (https://arxiv.org/abs/1609.04327) rather than directly to the PDF. From the abstract, one can easily click through to the PDF; not so the reverse. And the abstract allows one to do things like see different versions of the paper, search for other things by the same authors, etc. Thank you!