Every few months a new productivity app promises to change everything. I have tried most of them, and almost all of them ended up as one more inbox to check.
What survived is boring: a plain text editor for notes and drafts, a shared calendar for anything with a time, and a paper notebook for the daily plan. The notebook matters most — writing the plan by hand makes me choose.
The rule I follow now: a new tool has to replace an old one, not sit next to it.