Q: Anyone have problems with iPhone 5s freezing and switching itself off after ios8 update

Hey izzyweir,

Thanks for the question. After reviewing your post, it sounds like the iPhone powers off and does not respond. I would recommend that you read this article, it may be able to help you resolve or isolate the issue.

iPhone: Hardware troubleshooting

Will not turn on, will not turn on unless connected to power, or unexpected power off

iPhone is unresponsive and displays the Apple Logo

Thanks for using Apple Support Communities.

Have a nice day,

Mario