I have seen phone spelled as 'phone. Obviously this is an acknowledgement that the full word used to be telephone. Is this spelling objectionable?
I am assuming you are referring to the apostrophe that precedes the word phone as being the issue here. In this case, it is quite unnecessary as "phone" itself is a word. I have never seen the apostrophe before, and it would actually cause confusion as opposed to clarity to use this form.
According to the University of Sussex, this form is outdated.
Such clipped forms are not regarded as contractions, and they should not be written with apostrophes. Writing things like hippo', bra', 'cello and 'phone will, not to mince words, make you look like an affected old fuddy duddy who doesn't quite approve of anything that's happened since 1912.