Pretty much all the time. It is part of the alphabet, so don't take it for granted. In terms of writing kanji by hand or even typing (in informal settings), if a kanji has way too many strokes (and is a common word like "apple"), you'll see it written with katakana or hiragana instead. E.g. 蝙蝠 > way too many strokes, right? So it is often written as コウモリ. Another example; 林檎 is pretty much always written as りんご or リンゴ. But in more formal settings such as the newspaper, the kanji is much more likely to be used.