Akademik

a lightweight consumer electronic device that looks like a hand-held computer but instead performs specific tasks; can serve as a diary or a personal database or a telephone or an alarm clock etc.

ˌpersonal ˈorganizer f12 (BrE also -iser [personal organizer]) noun

a small file with loose sheets of paper in which you write down information, addresses, what you have arranged to do, etc; a very small computer for the same purpose

see also ↑Filofax