From 2017 to now
SimpleScheduler started as an Android app in 2017. Its Korean name is 심간표 (Simganpyo), short for “simple timetable”.
The iPhone app followed in 2018. A new version of the iPhone app is on the way.
Today the Android app has To-Dos linked to classes, three home screen widgets, a lock screen timetable and password-protected backup files. There is no sign-up, and timetables and tasks are stored on the phone.