Hi HN, I'm Minjae, a solo developer.

- About two years ago, I came up with an idea and worked on it as a side project for about three months, but I had to quit because I was overwhelmed by my main job.

However, when I recently used a coding agent to configure the specifications and have the development done, the implementation speed was incredibly faster than it was two years ago. So, I focused on refining the specifications and rode that momentum to launch the service in just two weeks.

- The reason I developed Velprium was the problem of my data being scattered across multiple places when recording my day. Calendar, Notion, Obsidian, and various other collaboration tools...

I even tried a paper bullet journal, but I failed every time I had to transfer notes between digital and analog formats.

That led me to think, "What if I added Notion's properties to calendar events?" Traditional calendars consist of an x-axis representing time and a y-axis limited to just title and description. So I added event properties to enrich the y-axis. Then I realized there's a third axis: z, the perspective. The same x and y look completely different depending on which lens you view them through — a diary, a work log, sleep tracking, exercise, personal schedule. This is where the concepts came from: a page is a z-axis (the perspective you're viewing from), areas are the parallel time axes that make up a page, and event properties are the y-axis.

- Additionally, I added relationships between events. For instance, if you cannot complete a task today and need to postpone it until tomorrow, there's a postpone button — it keeps today's event intact and creates a follow-up event for tomorrow.

This allows you to track exactly when you postponed the task, and since the change history is saved for each event, you can also see exactly when you decided to delay it.

One thing that didn't exist in the two-years-ago version is an AI query feature. Having implemented several text-to-SQL chatbots for work since last year, I felt the calendar should have one too.

For example, you can ask it to analyze how your sleep pattern changed over the past month based on sleep events recorded in the calendar.

(For reference, I use my self-made iPhone app, Auto Event Maker, to synchronize health data recorded on my iPhone with calendar events.)

- This app is currently free, and I plan to add a paid plan as the number of users increases.

This is because, while server costs are minimal, I feel that if a large number of users utilize the AI features, I'll have to pay for the tokens.

- I am not sure if this model is useful and easy to understand for others, or if it is adding too many concepts to a calendar.

This is the main point I want to verify. Of course, I created it and am very satisfied with it and using it well.

Two things I'd love feedback on:

1. Do you think the concepts of page, area, and event properties are suitable for a calendar app?

2. Does the onboarding (and the pre-made page templates) make these concepts click? Please try it and tell me where you got lost.

I really want to receive feedback from users who primarily use calendar apps and users who enjoy logging their lives.