Onseol: Countdown Widget

Onseol is a countdown app and D-day counter for the dates that actually matter — exams, weddings, birthdays, anniversaries, trips, due dates, deadlines. Add a date, choose how it should be counted, and put it on your home screen as a widget.

No account. No sign-up. Nothing is uploaded. Every event lives only on your phone.

THREE WAYS TO COUNT
• Count down — days until a date. The day itself reads D-DAY, Korean style: D-30, D-7, D-1, D-DAY.
• Days since — a day counter from a start date. The first day is day 1, so day 100 really is the 100th day.
• Every year — repeats yearly. Birthdays, wedding anniversaries and memorials, with the upcoming ordinal shown: the 3rd, the 10th, the 25th.

HOME SCREEN WIDGET
Pin any event and it lives on your home screen. Three widget sizes: a single large day counter, a three-line list, or a five-event list. It refreshes at midnight, so the number is already right when you wake up. Light and dark themes follow your phone.

LUNAR CALENDAR (음력)
Pick the solar date once and Onseol counts to its lunar date every year after that. Lunar birthdays, lunar memorials and traditional anniversaries stay correct on their own — no converting dates by hand each January.

MILESTONES, COUNTED FOR YOU
Every 100 days up to 1000, then 2000, 3000, 5000 and 10000. Onseol shows which one is coming next and can remind you before it lands: the 100-day milestone couples celebrate, the 1000th day, all the ones you would otherwise miss.

REMINDERS
Optional notifications at D-7, D-1 and on the day itself, at 9 in the morning. Set per event, off until you turn them on, and scheduled entirely on your device.

BUILT TO BE READ AT A GLANCE
Give each event a colour and an emoji. The list orders by what is coming next. There is nothing to configure and nothing to learn — add a date, see the number.

PRIVACY BY DEFAULT
There is no server behind Onseol. No account to create, no email to hand over, no profile built from your life. Your dates and titles cannot be sold, because they never leave the device. Delete the app and everything goes with it.

TYPICAL USES
Exam countdown · wedding countdown · birthday reminder · anniversary tracker · baby due date · vacation and holiday countdown · graduation · retirement · moving day · project deadline · payday · military discharge · sobriety and habit day counter · memorial day · pet adoption day · first date · new job · lease end · trip planning.

FREE AND PRO
The free version holds 5 D-Days and is supported by ads. You can watch a short ad to add one more — one ad, one D-Day. Onseol Pro is a single one-time purchase, not a subscription: unlimited D-Days, premium widget themes, every accent colour, and no ads again.

Onseol is a small, quiet app. It counts days, and it does that properly.