One thing I've found missing from the Pocket Rex app is alerts for any set reminders/appointments.

Eg, When you receive an inbox on Facebook, you get an alert.
( Tone, torch flash and notification panel ).

Right now, it seems the only way to be reminded of your appointments and reminders is by having the app open and constantly checking reminder times.
I currently work around this by setting an alarm on my phone for 15 minutes before the appointment so I get reminded of it.

Having a message tone, torchlight flash, ect, 10-15 minutes ( obviously would need to be able to set a custom reminder time ) before hand would've saved me missing phone calls, emails, ect.