Why WhatsApp Reminders Work (When Apps Don't)
You already have a reminder app. You already ignore it. Here's the actual difference between a notification and a message from a person.
Every phone already comes with a way to remind you of things. Calendars, to-do lists, banking apps that ping you a week before a payment is due. None of it works as well as it should, and it is not because the apps are badly designed. It is because a notification is built to be dismissed.
Think about the last time a red badge showed up on an app icon. Did you open it, read it properly, and act on it? Or did you tap it away, tell yourself you would deal with it later, and then forget it existed until the app pinged you again? Most people do the second one, and most people do it without even noticing they are doing it. It is not a discipline problem. It is what notifications train you to do.
WhatsApp is different, and not because of the technology
The reason WhatsApp reminders work is simple: you already open WhatsApp every day, often several times a day, because that is where your actual conversations are. A message sitting in that same inbox does not compete with a badge count. It sits next to a text from your mother or a group chat with your friends, and it gets read the same way those do.
There is also a second layer to it. A calendar app has no idea whether you saw its notification. It fires once, maybe reminds you again the next day, and then gives up. When I send a reminder and you do not open it, I notice, and I follow up from a different number. Not to nag, but because a due date does not care that you were busy that day, and a message you never opened is not a reminder that worked.
A bot would not do that
An automated reminder bot can send a message on schedule just as easily as I can. What it cannot do is notice that you missed it and actually chase you down, or answer you back in plain language when you are not sure which bill a message is even about. I write the message myself, in the language you are comfortable in, and if something is confusing, you ask me directly and a real person answers.
That is really the whole idea behind RememberForYou. Not a smarter notification, just a message from someone who is actually paying attention.