I’m Daniel Nguyen. Last year I quit my consulting job to start indie hacking.

The idea of KTool first came to my mind when I was reading “Ask HN: I’m a software engineer going blind, how should I prepare?” on Hacker News.

I’ve been wearing glasses since I was 5. My right eye is blind. Doctors said there is no chance to cure it.

I was genuinely scared. Like holy crap, if my left eye stops working, my life is done. Since then I’ve been very conscious about time spent on computer screens.

That’s when I started using Kindle-related products: to offload as many reading materials as possible to the Kindle. Then I ran into multiple limitations, leading me to build KTool, a tool to send your favorite online content to Kindle: blog posts, Twitter threads, Hacker News discussions, RSS feeds, newsletters…

I didn’t start it immediately. In the beginning, I tried to validate the idea by asking on Reddit. And the initial idea was a macOS app to send PDF & EPUB to Kindle. But after building it in public on Twitter, it’s clear to me that people won’t pay for it. So I kinda pivot into sending articles & Twitter threads to Kindle and got much better traction.

After 18 months it’s currently at $1,000 MRR with minimal maintenance cost. I spend maybe 4-5 hours per month on it.