App Tracker and Chord Reader go open-source
I recently open-sourced two of my Android apps – App Tracker and Chord Reader. You can find the code on GitHub.
I open-sourced them for very different reasons, although the catalyzing events were similar. In both cases, I had a request from a fellow dev for more information about the app, which made me question why I was keeping it closed-source in the first place. And in both cases, I couldn’t find a good reason to keep the code private.


Of course, a lot of code gets open-sourced, and a lot of it gets lost in the abyss of endless cyberspace. There’s no point in making a big show about releasing this code without explaining a bit about why anyone should bother looking at it. So here’s my brief run-down:
App Tracker reads the system logs (“logcat”) in a background Service and notes when other apps are being launched, which allows it to keep usage statistics. It should be interesting for anyone looking to write an app to detect when a third-party app has been started (which was the question from a fellow dev that prompted me to open-source it). For instance, all of the various “protect my apps with a password” security apps use this technique. Be forewarned, though: these methods are faulty, given that the Android OS treats with suspicion any Service that tries to run 24/7, and may kill your Service without warning.
Chord Reader reads chord charts downloaded from sites like AZChords.com and UltimateGuitar.com, parses the text, and displays information about the chords, including various guitar fingerings. The most interesting part is the system of regexes (really, a grammar) to parse the chords and determine, for instance, that “Abmaj7” and “G#M7” both mean the same thing: “A-flat, major quality, 7th added.” A good place to see this in action is the unit tests. Music geeks should get a kick out of it. And of course, anyone who just wants to contribute to the project (like the dev who first contacted me and suggested open-sourcing it) is welcome to create branches and pull requests on GitHub.
Oh, and in case I haven’t made it clear elsewhere, when I open-source something on GitHub, please assume that the license is the WTFPL license, or some other very permissive open-source license. I honestly don’t care what you do with the code, although hopefully you’ll be nice about it and give me credit. Happy coding!
Posted by Paola B on
Hi, Unfortunately Chord Reader does not work with NEXUS 7 or NEXUS 10. When searching/choosing a song from search you get a Blank Screen displayed that goes no further.
Posted by Nolan Lawson on
Yep, it’s a well-known bug. I would love to fix it, but unfortunately I have already spent lots of time on it without making any progress. Seems to be a fundamental problem with WebView introduced in Android 4.0.
Posted by Jerry on
Hello Nolan,
I know this is an old post (2012) but I just want to say thank you for your app (Chord Reader 2) that help me a lot in 2026 !
Thank you to open-source it.
Unfortunately, I don’t have enough money now but, maybe, one day, I could pay you (I hope).
So again, thank you so much.