Just yesterday, I was at the grocery store and needed to check my shopping list on my phone. When I unlocked my phone, I found that it had (entirely on its own) connected to the insecure store wifi, and was downloading a 1GB+ update package. I was unable to stop this download, and it warned me that if I left wifi range it would continue the download over mobile data. Immediately upon finishing the download, the phone displayed a full-screen countdown stating that it was rebooting to install the system update.
Reluctantly, I gave up on checking my shopping list, placed my phone back into my pocket, purchased the items I could remember adding to the list, and went home. I have no idea how long the installation took, but the next time I checked my phone, it had successfully installed the update.
This is exactly the type of thing that makes me despise technology.