Hi HN! I’m Johan. I built Dlog, a journaling app with an AI coach that tracks how your personality, daily experiences, and well-being connect over time. It’s based on my PhD research in entrepreneurial well-being.
Edit: here's a video demo so you can see it before downloading: https://www.youtube.com/watch?v=74C4P8I164M - it's unvarnished but I'm told that's how people like it here :)
How Dlog works
- Journal and set goals/projects; Dlog scores entries on-device (sentiment + narrative signals) and updates your personal model.
- A built-in structural equation model (SEM) estimates which factors actually move your well-being week to week.
- The Coach turns those findings into specific guidance (e.g., “protect 90 minutes after client calls; that’s when energy dips for you”).
- No account; your journals live locally (in your calendar). You decide what, if anything, leaves the device.
The problem
- Generic AI coaches give advice without understanding your personality or context.
- Traditional journaling is reflective but doesn’t surface causal patterns.
- Well-being apps rarely account for individual differences or test what works for you over time.
What my research found (plain English)
In my PhD I modeled how Personality, Character, Resources, and Well-Being interact over time. The key is latent relationships: for example, Autonomy can buffer the impact of low Extraversion on social drain, while time/energy constraints mediate whether “good advice” is actionable. These effects are person-specific and evolve—so you need a model that learns you, not averages.
The solution
Dlog pairs on-device journaling analytics with an SEM that updates weekly. You get a running estimate of “what moves the needle for me,” and the Coach translates that into concrete suggestions aligned with your goals and constraints.
Early stories (anonymized from pilot users)
- A founder saw energy dips clustered after external calls; moving deep work to mornings reduced “bad days” and improved weekly mood stability.
- A solo designer’s autonomy scores predicted well-being more than raw hours worked; small boundary changes (client comms windows) helped more than time-tracking tweaks.
Tech & security
- Platform: macOS (Swift/SwiftUI). Data: local storage + EventKit calendar for entries/timestamps.
- Analytics: on-device sentiment + narrative features; SEM computed locally; weekly updates compare to your baseline.
- AI Coach: uses an enterprise LLM API for reasoning on derived features/summaries. By default, raw journal text does not leave the device; you can opt-in per prompt if you want the Coach to read a specific passage.
- Why 61 baseline variables? The SEM needs multiple indicators per construct (Personality, Character, Resources, Well-Being) to estimate stable latent factors without overfitting; weekly check-ins refresh those signals.
What I’ve learned building this
- Users value clarity with depth: concise recommendations paired with focused dashboards, often 5–10 charts, to explain the “why” and trade-offs.
- Cold start matters: a solid baseline makes the first week of insights credibly useful.
- Privacy UX needs to be explicit: users want granular control over what the Coach can read, per request.
I’m looking for feedback on:
- Onboarding (baseline survey and first-week experience)
- Coach guidance clarity and usefulness
- Analytics accuracy vs. your lived experience
- Edge cases, bugs, and performance
Download: https://dlog.pro
If you hit token limits while testing, email me at johan@dlog.pro
Background
PhD (Hunter Center for Entrepreneurship, Strathclyde), MBA (Babson), BComm (UCD). I study solo self-employment and well-being, and built Dlog to bring that research into a tool practitioners can use.
Note: The Coach activates after your first scored entry. If you haven’t written one yet, you’ll see a hold state—add a quick journal entry and it unlocks.
Appearance: On a few Macs the initial theme can render darker than intended. If you see this, switch to Light Mode as a temporary workaround; a fix is incoming.
You may enjoy the 2024 Hugo winning short story, "Better Living Through Algorithms": https://clarkesworldmagazine.com/kritzer_05_23/
I'm a bit intimidated by the long list of things this app is trying to do.
Is it a project management tool? If so, how do I share everything with my team? Project management tools are defined by their collaboration and workflow features.
Is it a journaling tool? If so I absolutely don't want my team in the tool, and so can't use it for project management. How does it encourage me to do better journaling and build the habit?
Is it a wellbeing tool? How well does that work if I don't put my project management in there? If I can't use it for half the stuff it's intended that I will, then it might be of limited use.
Is it a coaching tool? Why would I want to use an AI coach over a mentor or human coach?
Is the AI required? I have no idea how many tokens I'd need to use something like this? Do I need a million a day or a million a year? (When coding I tend to use ~10-50m input tokens per session, will this cost $500 per day to use?) If the AI features are optional, what is the product without it?
Overall my feedback is that there's a lot here, and I think the product needs a much clearer story. The copy on the site is long and rambling and needs a lot of tightening up. Personality is good, but in moderation.
Questions while watching the video.
Calendar is central, but I use a Google calendar which is important to me. Connect it?
Seems like a "dlog" is a calendar entry. So is my "journal" broken up into separate pages, not a sequential document or blog?
2:30 ff, strongly suggest that for your next video you pre-script it to avoid fumbling and mumbling.
5:10 side note, interesting that your personality(?) model was from 2018, well before LLMs.
7:50 for an app to produce such output (impact of a friend on mood) you surely must do a copious amount of extremely frank journaling. When, and in what format? As scattered calendar entries? I'm confused how I fuel the app.
10:40 relating diary entries (reported activities and attitudes) to one's stated goals -- this is what I would expect an AI to do, and tell me about them rather than the reverse.
I'm sorry, I just don't see how I could use or adapt to something like this when I have a well-established diary/blog and calendar, it would mean changing many daily habits and adding what looks like a lot of detail work.
I love the vision. From what I can tell, you're building something that I think should exist and we have the technology for now. I think we need a place to put our 3, 5, 10 year goals, and some kind of process to keep us on track for that. And it's so personal, of course the LLM aspect needs to be local-only.
One concern I have is that I think I will need more than an empty "add Journal entry" nudge or prompt. I think I would want what a real coach would do/say. Something like, "How's the meditation/exercise/calling friends/making stuff going?"
I like the concept, but I bailed at "GPT 5". The only thing that has given me peace of mind and the ability to journal honestly and successfully is Obsidian, because it lets me own my data (as text files).
First comment: I freaking love your privacy policy. Seriously. Great job!
Second: I haven't downloaded it yet because my itsatrap.gif warning bells are going off about pricing. On a scale of free to kidney, what are we looking at here? Is this going to be priced for end users, or will it look closer to an enterprisey kind of plan?
Hey kstrauser, thanks for the first comment!
Can you let me know what would reduce the warning bells regarding the itsatrap.gif? Like, what gave you that impression? Really need to get this right.
For general users it's free for 14 days with 10K free tokens; then its 1.99 per month at the moment.
However, if you or HN readers that DM me or email me with the email they register with, I'll give a free perpetual license so there's no monthly fee; and add 1 million tokens.
Thanks again for the feedback, I'm glad you liked the privacy policy! :))
Oh! That's pretty reasonable. It's just that I've seen so many slick looking tools that go for waaaaaaayyyyy more than I'd ever personally consider paying for them, like "use AI to sort your CD collection for only $29.95 per month! For only a cup of coffee a day, you could have perfect sorting!"
Do you support Bring Your Own Key (BYOK)? If I'm the first to ask, I'm 100% certain I won't be the last. That a standard question we get from our own customers.
OMG that's ridiculous. I will definitely look closely at integrating BYOK. Do you have an app that uses BYOK?
That might've been an exaggerated example, but only a little! I've seen lots of tools add AI as a feature and immediately jack their prices.
Sure, lots of apps do that. For example, Zed (https://zed.dev/docs/ai/llm-providers) has a subscription plan but alternatively will let you plug in your own key and then provide the same features free of charge.
Also, I added the pricing to the home page; hopefully this reduces those warning bells! Thanks so much, I hadn't considered that that would be a barrier.
Should include systems requirements on the download - I got a grumpy MacOS message about needing to do an OS update to run it. It's not a big deal but little frictional hiccups like that results in invisible abandonment.
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