In German, "tippen" is a possible translation of "to guess". There's a well-known tradition of friendly betting on football matches with colleagues or friends (sometimes with money on the line, often not). These are called "Tippspiel" or "betting games".

> In English too - think "betting tip".

A betting tip is when someone gives you information relevant to a bet.

That is a sense that definitely exists in English, but obviously there is no such thing as a "tipping competition" in this sense.