Commaday: One Line Journal

A note first: the app's interface is entirely in Korean. There is no English UI yet. If you read Korean comfortably — or you're learning and want the immersion — it works as-is. I'd rather you know before installing. Inside the app you'll see its Korean name, 낙서장씨.

How many journals have you started and left behind?

Commaday is a diary built around one line a day. Too long to write, too imperfect to post, so you put it off — this app starts from the smallest habit instead.

■ One line a day
One sentence is enough. You can attach a photo if you want. On days when nothing comes to mind, a prompt is waiting: 66 sentence prompts and 60 words run on separate cycles, so a given pairing takes nearly two years to come back. You can ignore both and write freely. If you'd like, a quiet reminder arrives each night at a time you choose. You can change it in settings.

■ The comma that keeps you going
Write daily and your streak builds. Every seven days you earn a comma, and you can hold up to two. If you're running low, you can earn one by watching a single ad. Take a day off and a comma fills it in for you. And if a streak does end, every entry you wrote stays exactly where it is — nothing is deleted, and nothing counts down to a next goal.

■ Your time, gathered on a calendar
The days you wrote are joined by a golden thread across the calendar. Look back after a month and the single lines have quietly become a story.

■ Your writing stays on your phone
No account, no sign-up, no server of mine. Everything is stored on your device. An optional Google Drive backup lets you move your entries and photos to a new phone.

■ Premium (optional)
· All 3 ways in one day — Freeform, Sentence, Word
· 3 photos per entry
· Write your own prompts and keep them
· Export as PDF — each month on one calendar cover

A one-time purchase. The free way you've been writing stays exactly as it is.

Tonight, just one line.