Kosmogram NusantaraBatak
Once carved onto bamboo slats by a datu.
12Sipaha months
30day names
Today
—
The moon is —
Most of us only know one. Across the archipelago there are many ways of counting a day — and most of them are still running right now, only nobody tells us.
Free · iOS & Android · Indonesian
Kosmogram shows them all at once, for today, where you are. Not a history lesson — something that is running today as well.
Nusantara calendars
Switch whenever you like. What changes isn't only the name of the day, but how the season is read and how a good day is marked.
Once carved onto bamboo slats by a datu.
A five-day pasaran meets a seven-day week.
Still legible in old Sundanese manuscripts.
Ten wewaran cycles run at the same time.
Marks Imlek and Cap Go Meh.
Sky Rhythm
A single arc draws your whole day: where the sun comes up, where the moon follows, when each of them touches the horizon. Computed for your own location, not the nearest city.
Sky Map
Taurus, Gemini, Cancer — drawn with their connecting lines, in the right position for where you are standing tonight. There's a compass in the corner of the screen, so the map in your hand lines up with the sky above you.
Drag the timeline and the sky moves with it — back to this afternoon, or forward to three in the morning.
Daily reading
Four every day — love, work, social, family. Each closes with one thing you can actually act on, not advice left hanging. Here is one of them, exactly as it comes out of the app.
An actual reading from the app
1 · Love
Good moments slip past easily when nobody writes them down. Remembering the small results helps a relationship feel like enough, without spending energy on proving something new.
Write down three good things from this week, then send one to your partner.
Like the reading? Turn it into a card, then send it to whoever came to mind while you read it.
Puspa
Every time you open Kosmogram, read the day, or write a reflection, you collect dew. Dew waters Puspa, and Puspa moves up a stage — from Shoot to Sprout, slowly.
Miss a day? Puspa simply stops growing. It doesn't die, nothing is charged, and no notification blames you for it.
Where it comes from
Kosmogram is assembled from the Perpustakaan Digital Budaya Indonesia collection together with Bandung Fe Institute — a group researching complexity, culture, and computation.
Pricing
Rp12.000
About Rp52,000 a month. Good for trying it out.
Rp28.000
Less than a thousand rupiah a day.
Rp280.000
Works out to Rp23,333 a month — 17% less than monthly.
Before you download
No. The readings come out of ethnoastronomy — the way communities across the archipelago read the moon and stars to mark planting, ceremony, and shared work. Treat it as something to think with, not a certainty about the future.
To compute sunrise and sunset, day length, and the weather where you are. Without it, the numbers in Sky Rhythm won't match the sky you actually see. The details are in Data Safety on Google Play and App Privacy on the App Store.
No. The app is free to download, and the subscription is optional.
Five to choose from inside the app, four of them Batak, Javanese, Sundanese, and Balinese. You can switch at any time. Want to go deep on one tradition? The same publisher also releases Kosmogram Jawa, Sunda, and Bali separately.
iPhone and iPad on iOS 15.0 or later, and Android through Google Play. Light, and usable the moment you open it.
Start today
Free to download. One minute tomorrow morning, and see for yourself whether the day feels a little different.