Using an iPhone so default notes app is more than sufficient for my note takind needs and with me and wife sharing iCloud account, we have common notes.
Calendar5 for my reminders as I am super bad at remembering things and this app is super useful for me. I think I even paid for it.
Television Time for managing tv shows tracking. I know title says productivity but since I spend 3+ hours in to and fro office travel daily, I heavily use my tablet to watch TV shows and poof goes away all my worry about traffic jams etc.