PTIJ: What is the Torah preferred brand of cell phone?

I have heard of Kosher phones. What do the classic sources (preferably Rishonim or earlier) say about the preferred type and brand of cell phone?

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Answer

The rule is:

שלא יוציא אדם דבר מגונה מפיו ולעולם יספר אדם בלשון נקייה

Never use a Magna and always use a Nokia.