I miss many calendar reminders because they're just too subtle. I might put my phone down and walk out of the room for 5 minutes, missing the reminder, then come back and not touch my phone again for an hour; completely missing an important appointment.
If reminders worked like alarms, they would make their notification sound continuously (up to a point, like alarms: ~10 minutes), and take over the whole screen, until silenced. That would be preferable to me. Is there an app that can do this?