Capture is only the front door
A GTD tool fails if it stops at quick capture. The hard part is helping users clarify, organize, review, and choose actions when life gets noisy.
Weekly Review is the retention engine
The Weekly Review is where the system becomes trusted again. It deserves first-class product treatment, not a buried checklist.
Integrations should reduce inbox sprawl
Apple Reminders and Google Tasks support matters when users already capture work in multiple places.