Free and/or open-source tools I like

Jonathan Niles

08 Jul 2026 — 1 min read

Occasionally, I come across some really nice free and/or open-source tools that I feel work well for what I need. I'll add them to this list:

FairScan - scans PDFs using the phone camera
Immich - photo backup solution
Catima - loyalty card wallet, but I use it for any barcodes.
Signal - private, encrypted messaging.
StreetComplete - OSM surveyor app.

Below, I'll describe how I use them.

FairScan

This is such a nice application for low-resource settings. You can generate high-quality, multi-page PDFs from images, including with black-and-white options. I generally use these to scan signed documents to send via Signal or WhatsApp.

Immich

I currently do not use Immich to its full potential, but I could conceivably do so when I finally get around to degoogling my life. Currently, I use it as a self-hosted photo backup solution.

Catima

I replaced my YMCA application with this to avoid all the spam push notifications. I also used it to replace my library card, but I mostly use my card to scan for printing and it doesn't work super well for that use case. I wonder if an eInk display would be better for replacing ID cards.

Signal

I wish I could replace all my needs with Signal, but the network effects are too strong. Instead, I use Signal for notes to self, and a few trusted confidants. I also was able to use Signal as a private notification server for my HomeAssistant instance.

StreetComplete

Such a great application for anyone who is civically minded! StreetComplete allows you to complete "quests" to fill in missing data on OpenStreetMap. You walk around your neighborhood and fill in missing information, including whether there are signals, lined crosswalks, the pavement type of the road, accessibility options, missing house numbers, etc. Along the way, you earn points and badges in a classic gameified approach. I cannot recommend it enough.

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