"My sister spoke with her friend over cell phone."
Translation:Mi hermana habló con su amigo por celular.
Why amigo and not amiga?
For some reason, Duolingo is only accepting "amigo" for "friend." Both amigo and amiga should be accepted.
Is it possible to reverse the phrases in Spanish?:
"Mi hermana habló por celular con su amigo."
I would say ¨over the phone¨ but never ¨over cell phone¨ but i would use ¨by cell phone¨which DL does not allow. In English you can always talk ¨by¨ the instrument you use (by phone), you can go ¨by¨the method of travel (by car) and die ¨by¨the cause of death (death by homicyde).
A little frustrating that suddenly we cannot use a core principle of English.