Tectra Systems

Home of programmer John Spahr's computer-related creations!

Welcome to my site!


About Me

Hi, I'm John! I started seriously programming back when I was in 6th grade, and I have worked with many different languages and platforms over the years. I started with C# but I have also spent a lot of time working with Kotlin, Java, Visual Basic, Swift, and JavaScript. I have used these programming skills to write apps for all sorts of platforms, old and new. These include Android, iOS, Windows, Wear OS, Palm OS, webOS, BlackBerry OS, and Windows Mobile!

My hobbies include programming, tinkering with computers, reading, writing blog posts, and spending time with my cats.

Social Stuff

 GitHub  Twitter  YouTube john [at] tectrasystems [dot] org

Some of my main projects...

Violoncello logo


A powerful text-based browser with lots of features and a sleek user interface. Available for Android and Windows, Violoncello can run on all sorts of devices!

 Android  Windows

Compliment Moi logo

Compliment Moi

A fun app that takes a photo of you and gives you a compliment! You can choose from different compliment lists to keep things interesting.

 iOS  Android

TaskNudge logo


Set a single, short-term task for yourself and get reminders every few minutes to complete it. If you have trouble remembering to do a quick task or have difficulty staying focused, you'll likely find TaskNudge helpful!


LifeBoard logo


Meet LifeBoard, your own personal bulletin board! Create quick notes, categorize them, and get stuff done.


SpeechLab logo


A simple and ad-free text-to-speech app.

 Android  Wear OS

binoc logo


Start something with an image, quote, and intention for yourself.

 Android  Windows Mobile

PDF Toolbox logo

PDF Toolbox

A powerful and completely free tool that lets you split, merge, create, remove pages from, and compress PDFs.


Syndicate logo


A powerful and easy-to-use RSS feed reader with lots of customization options.


Circle Calculator logo

Circle Calculator

Calculate the circumference, area, radius, and diameter of a circle.

 BlackBerry OS  Palm OS  webOS

Tectra Dice Roller logo

Tectra Dice Roller

Roll dice.

 Wear OS  Palm OS

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© John Spahr 2021