S Planner is a very good app that comes with android phones who have android versions of 2.3 and more.The size of the app is just 12 MB and you can easily download the app from the Play Store as well.
As far as the Samsung phones are concerned,this app is generally already installed when you buy the phone.The app is very useful in storing reminders,important events and meetings.The UI of the app is very simple and one could place reminders within seconds.
As soon as a reminders date and time is reached,a display with the reminder message comes on the home screen of the phone along with an alarm.
I found that it is best used for storing the reminders only.
I found this app good and hence I would like to give this app 4 out of 5 stars.