On ANA flights, I have seen that flight attendants use a mini notebook they keep in their uniform pocket

. Very regularly, they go through it, and write things. I wanted to ask them what they write about, but found no occasion, as they were always busy when I thought of asking. I guess they read about all the different things they have to do, go through their work process, and take notes about everything they have done and still have to do...?
As they all do it, I do not think it has to do with personal notes. I saw photocopies, check lists and various lists and charts in the notebooks.
Can snybody tell us about this? Thanks!