Is there a "perfect" GTD app?

- Under $5/ month (or equivalent), bill monthly

- Inbox list as "capture"

- Tags & SubTags for Next Actions, Waiting For, Projects, Higher Horizons, Someday/ Maybe, etc.

- Lists $ Sublists or Projects and Sub Projects for housing projects and their tasks together in one place (all tags might have dates and tags)

- Priority list

- Calendar view (weekly and monthly) for Lists, Tags.

- Kanban Board

- Tasks with the ability to add dates (start and end), priority, tag, list

- Gantt View on Lists (Projects)

- "Today's View" with Kanban View and List View

- A view where today's tasks and this week's tasks can be viewed together with calendar events

- Calendar sync with personal, professional, and client-provided calendars

- Can be accessible through web apps, iPhone and Android mobile apps, Mac and Windows desktop apps

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I use TickTick at the moment and I am surprised that there is nothing out there that satisfies all the of above. AND those apps are more expensive than TickTick.

TickTick does not have:

- A good and responsive calendar sync (its really annoying)

- A Kanban View for "today"