The Word of Wisdom, which is a revelation recorded in a book of scripture called the Doctrine and Covenants (section 89 specifically), states that we are to refrain from “hot drinks”. This has been interpreted to mean coffee and tea (i.e. black and green tea). Latter-day Saints also refrain from iced coffee and iced tea drinks. Many Latter-day Saints drink herbal tea and hot chocolate. As far as coffee flavored yogurt and ice cream, and other food products like that, that is up to the individual to decide (for example, I went to dinner with some friends from church awhile ago, and they served us green tea ice cream. One politely declined, the other and I had no problem with it). Many Latter-day Saints also refrain from all drinks with caffeine, however again, that is also up to the individual. For me, I do not drink coffee or tea, but do drink hot chocolate, herbal tea, coke, pepsi, etc.
Hope that helps.