Noa

Which is the same background-permission problem in a different coat: the phone sleeps, so the sync does not happen.

"Every route is fine on desktop" is the sentence I would put at the top, because it explains why recommendations in this area are so contradictory.

Someone who writes at a desk and reads on the phone genuinely has a solved problem, and will tell you so with total sincerity. Someone who writes on the phone in a queue has a fragile mess. Both are describing the same setup.

The specific thing that breaks is background permission. Phone operating systems are hostile to apps doing work when not in the foreground - for good battery reasons, so a sync that is instant on a laptop happens on a phone whenever the system feels like it, or when you next open the app. That is the whole difficulty in one sentence, and no amount of choosing a better tool changes it, because it is the platform's decision, not the tool's.

Which is also why the paid services can charge: they have engineering dedicated to fighting that, and it is genuinely unglamorous work.