I write songs several different ways. Sometimes it starts with a melody or a lyric. I find the voice recording app on my phone to be extremely useful in this regard. I can record a line pause and continue recording as I go. Sometimes I can work toward rough versions of songs listen to them back easily without having to worry about more complex recording software. It honestly is wonderfully convenient and sometimes produces pretty reasonable recordings. The added benefit is I can quickly send a rough version of a song off to a friend.
When you need to quickly record something, what do you use?