Choosing between SMS and push notifications depends on how quickly the message needs to reach users and where they are. SMS reaches people even when they are not using data or do not have the app open, so it works well for very important alerts like payment issues or time-sensitive confirmations. Push notifications are better for app-related reminders that are helpful but not serious. SMS feels stronger and should be used only when needed because it can interrupt the user. Push notifications are easier to ignore, so they must be clear and direct. Both should stay short and respectful. Which method do you feel works better for urgent communication in most apps?