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Show HN: How Are You-elderly fall detection app I built solo with AI in 6 months
4 points by sminchev 47 days ago | hide | past | favorite | 10 comments
I am writing the post, because I want to show that with AI, really complex and meaningful projects can be done, if the proper tools were used the proper way. I needed a project that I can use, so that I see how far I can go with only AI usage. I needed something doable, but relatively complex. And then I remembered an idea my wife shared with me, a few years ago: an app that monitors her grandfather's behavior and sends a notification if he stops moving. at that time, AI integrations were not considered as an option, and static algorithms to model behavior (with adaptation) were complex and fragile. I am not that smart to implement such thing.

I started in December 2025. I read a lot, watched videos, I found a AI framework that I wanted to try: BMAD. The idea behind it felt known to me. Agile methodology, but with agents. What can go wrong!? I had all I need. A language that I don't know, Android OS, that have changed a lot for the last 15 years , and AI models that I can use to dynamically adapt the behavior changes. A chosen framework. Looked complex enoungh for me. So many unknown things. The only thing I had was my experience in the software development! I needed one week to go through the BMAD worklflow and get all documentations out of it. The main plan was to ask AI to implement the detection of the following concerns: * Unusual stillness (potential fall or medical event) * Did not wake up on time * At an unfamiliar location at an unusual hour * Phone silent for too long

I ended up with the following technical stack:

* Kotlin + Jetpack Compose + Material 3 * Room + SQLCipher for encrypted local storage * Google Gemini for behavioral analysis * Resend API for transactional email alerts * Clean architecture: :domain (pure Kotlin) -> :data -> :ui -> :app

Having the basis known to me and the AI, the next five weeks the dev agents did the implementation.

And when I started testing, ALL FAILED. All was there, but nothing was connected. Like, 20 devs did something without a single daily meeting, ever! I think that, if I tested more in the middle phases, knowing and checking the code regularly , investing more time in the initial BMAD workflow steps, I would have gotten better results. I also tried different models, before sticking permanently to Opus.

I didn't stop. Weeks of testing and fixing. What I learned the hard way: Android dev isn't as enjoyable as it used to be. Every OEM has its own way to kill my 24/7 monitoring With AI and multiple LLMs, I ended up with an 11-layer service recovery system: * Foreground service with IMPORTANCE_MIN channel * WorkManager periodic watchdog * AlarmManager backup chains * BOOT_COMPLETED receiver * SyncAdapter * Batched accelerometer sensing * Exact alarm permission recovery * OEM-specific wakelock tag spoofing * START_STICKY restart * Safety net AlarmClock at 8-hour intervals * User-facing gap detection with OEM-specific guidance And new issues came up every day :D

And here are metrics: 422 prod files, 87k+ lines of prod code, 2251 tests, 53k+ line of testing code.

Was it worth it?! With all the unknowns and mistakes, it took me 6 months. My investment so far is mostly the Claude Max subscription. Old-school, that's 2-3 people for the same 6 months. Would I do it again? Yes. I know what to do now: pick a language I know, test more often, review the code often, write better docs. Use the right tools and LLM. Is the code quality good? Honestly, I don't care. As a PM, I care about fast delivery, low cost, good performance, stability, documentation. If the code were bad, I wouldn't get those. The app shipped and looks stable — so the code is in decent shape. And seeing how Claude Code works, the code is full of comments. Ordinary devs don't document this well. From that angle, the code is excellent!

The website (AI generated) : https://howareu.app/ Any advice, feedback, opinions will be highly appreciated.



I'm also developing solutions with this, and everything will depend on how you contextualize the agents so they understand how your product should work within your market vision. Generating consistent and decent code works, but you need to manually persist (for now) the operational principles and inviolable fundamentals of your program. Bugs will always appear, but the speed of implementation is impressive and, in practice, becomes cheaper than hiring an entire team of developers.


Yes. you can't just leave it and go somewhere. Constant monitoring is required


Wow, you spent a crazy amount of time on something an experienced dev could hack together in a weekend without AI, and probably as little as a day with Claude Code.

This is like an anti-ad for AI and vibe-coding.


I doubt. Experience dev can't make 400+ files and write 2000 tests in a weekend. At least, I was never that fast and productive ;)

With my experience, developing android apps in Java, 10-15 years ago, such project would need at least 2 developers, for 5-6 months of development and testing.


An experienced dev wouldn't need 400 files and 2,000 tests just for this.


I think that you are underestimating the complexity. You need to deal with the specifics of different OEMs. You need to be absolutely sure that you are covering all cases, where the OEMs can stop the app. Testing and fine-tuning took more time, than I really expected

Then monitoring itself is not that easy as well. You need to distinguish between a planned vacation trip, and visit to a friend. And a lot, a lot more things.

To be honest, yes, it took me more time than expected. And now, with my current knowledge, next time, I will do it much, much faster, with less token. But this is how it is with every development. A junior developer will waste more time and money that an experienced one. With AI, most of us are like junior developers.

Most of the time, I waste, not with the app itself. But to keep it running 24/7, without in any way asking the parents to do any manual work. And this is because I did not know that Android based OSes are so aggressively killing long-running applications. I took my note :)

But to write it for a weekend, I just cannot agree. For a weekend, you can't make real and deep testing. A simple example: you need to run it for a few weeks, without opening it to see if Android will kill it, because it treats it as 'never used' app.


does this go on your phone, or do you need a smart watch, or what? did you actually do any physical testing?


The idea is a children to install it on their parents devices and do nothing more. No smart watch, no need to the parents to frequently click anywhere. Just keep their device with them. I did it that way on purpose. To be as less intrusive as possible. The app stays there and run 24/7 and detect locations, moment of activeness and rest, sleep, and creates behavior patterns. If any of the pattern gets violated, it send a notification. I give an example: my father do a daily walk between 8AM and 10AM. If he misses that one I will receive a notification. If my mother fails on the street and she does not move for some time, I will receive a notification with the exact coordinates.

That simple ;)


> Is the code quality good? Honestly, I don't care. > The app shipped and looks stable — so the code is in decent shape

not generally things you want to fuck with when making claims about health or safety.


:) It will be really stupid from my side to just let it go, without being sure that it will work. I am a professional after all, with almost 20 years of experience. There are 2000+ tests, 50K+ lines of testing code. I tested myself, and a lot of other people tested, with different devices. Covering all cases that we can think of. This is serious project, that I really hope that it will help a lot of people, and I really invested a lot of time and effort to make it stable. I intentionally delayed the push to production with a few weeks, so that I am 99.9% sure that I covered everything.

Of course, we are human after all, and I will highly appreciate every effort and support from others, so that we can make the product do better. :)




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