Everyone would need to plan their scheduled calls or sometime they would like to show other people to someone is calling them to go out !
You could create alert or call alert by selecting person from contact list or entering details.
When alert time comes and If you choose call alert then your phone start playing ring tone with alert message. So, Everyone around you could start thinking your phone is ringing. If you select call button on alert message then application will start to call that person and you could start conversion with that person after he/she answered the phone call.
On the other hand you may really need to call someone on sometime.