First, to the last part...
If they're vessels (like cups and spoons), they're clearly forbidden in the various authentic ahadeeth.
Now to the main part about other than utensils...
Let us first recall the hadeeth from Saheeh al-Bukhaari:
Al-Halaalu Bayyin, wal-harramu bayyin...
الحلال بيّن والحرام بيّن...
The hadeeth basically explains that the halaal is clear and the haraam is clear. And between that are the things of doubt. So as a general rule, we'd better avoid what is of doubt.
Now, a phone may seem (at first) like a piece of equipment. But then you're going to have to carry it with you. And most people don't just carry a phone. They' (almost) wear it. Either on their necks or on their waste and so on.
So although you're not intentionally wearing it, it's leading to that.
Furthermore, if you take things like spectacles, you're directly wearing it. So this is no different to wearing a necklace.
In conclusion, although there aren't ahadeeth about mobile phones and spectacles in particular, it's best to avoid getting into something that is doubtful.
Wallaahu a'lam.