"prefer on" is not correct and it is not a usable phrase in written English.
You can not use it. If you are trying to express a preference for something, you can use the phrase "prefer to" as in the following examples: I prefer to take a taxi rather than the bus. She prefers to eat Italian food rather than Chinese food.
The ads run in a bunch, or a pack, if you prefer, on one unspecified day in the last week of every month.
"What I prefer on a man is really just this," one woman said, pointing to a mannequin with a full beard, full armpit hair, full chest hair and full pubic hair (OK ― she cut back the mustache slightly, "for access purposes").
He wrote to one of the museum's curators: "I should prefer, on account of the row I had with the lady years ago, that the picture should not be called by her name".
"Women can't be blamed for wanting to be independent and self-sufficient, but smart ones have done so without diminishing the males whose shoulders they might prefer on imperfect days.
Or, if you prefer, on your legs.
"I don't think there's anyone in the league we'd prefer on the mound for our team and in this situation," third baseman Mike Lowell said.
For teen-age social-media users, who generally prefer on-the-go mobile applications, like Instagram and Snapchat, the self is the message and the selfie is the medium.
So it's changing the News Feed to prefer on-going broadcasts.
Today, the company plans to build on its success with three new headphone models catering to cost-conscience consumers, athletes and people who prefer on-ear solutions.
While to some extent viewers may just prefer on-demand programming, Hulu thinks its interface may have also limited discovery of live TV in some cases.
We would prefer on-site interview when conducting satisfaction survey due to its better success rate and because it is arguably easier and less costly to administer compared with phone-back interview.
