No moat. Still in business.

0

An iPhone app that takes Japanese learners from beginner to fluent with one new sentence per flashcard and spaced review.

Since 2015

Courses and learning · Individuals and families

0

Excel add-in for querying tables with SQL, scripting workbooks in C# and building custom Excel functions.

Since 2016

Free plan · Data and spreadsheets · Developers

0

A service that finds and quarantines flaky tests, skips unneeded CI jobs and runs a merge queue for software teams on GitHub.

Since 2021

Developer tools · Developers

0

Fixes the mixed content and insecure content warnings a WordPress site shows after it moves to HTTPS.

Website builders

0

Video player for language learners that shows two subtitle tracks at once, generates subtitles and translates them live.

Free · Video and audio · Individuals and families

0

Gets and renews free Let's Encrypt SSL certificates on cPanel shared hosting without command line work.

Free plan · Security and passwords

0

Lets developers share live progress of scripts and jobs through a link, via an API or a tqdm replacement.

Uptime and monitoring · Developers

0

A browser extension that saves and highlights words you look up on web pages, then drills them with flashcards.

Since 2020

Free plan · Courses and learning · Individuals and families

0

Desktop data analysis app where you ask about your data in plain English and get Python code, charts and notebooks run on your computer.

Since 2017

Data and spreadsheets

0

Flash card app for learners to keep their own word lists and practise them with spaced repetition on Apple devices.

Courses and learning · Individuals and families

0

Mobile app where learners practise speaking a new language with AI characters and get pronunciation scores.

Since 2024

Courses and learning · Individuals and families

0

Ad-free app that teaches children aged 3 to 14 one of 19 languages through listening, speaking and reading along.

Since 2024

Free plan · Courses and learning · Individuals and families

0

Runs performance benchmarks in your CI and flags slowdowns on each pull request, for software teams.

Since 2023

Free plan · Developer tools · Developers

0

Browser extension that swaps sentences on the pages you read into the language you are learning, scaled to your level.

Since 2024

Subscription · Courses and learning · Individuals and families

0

Teaches English, Spanish, French and other languages through song lyrics, with spaced repetition for new words.

Since 2024

Courses and learning · Individuals and families

0

Tracks test coverage over time for your repos and flags untested code, free for open source projects.

Free plan · Developer tools · Developers

0

Helps intermediate language learners reach fluency through spoken chats with an AI tutor, corrections and daily articles.

Courses and learning · Individuals and families

0

Runs code benchmarks on dedicated bare metal machines and flags speed regressions in pull requests before merge.

Free plan · Developer tools · Developers

0

Flashcard maker that schedules reviews by spaced repetition, with dictionaries and text to speech for language learners.

Since 2024

Free plan · Courses and learning · Individuals and families

0

Listening drills that help language learners catch spoken numbers, phone numbers and clock times in over two dozen languages.

Courses and learning · Individuals and families

0

Spreadsheet that links to databases and files and lets AI write the formulas, Python and charts for you.

Since 2023

Data and spreadsheets

0

An app for learning Japanese with an AI tutor, speaking roleplays, kanji, quizzes and a personal study plan.

Since 2026

Free plan · Courses and learning · Individuals and families

0

A language app that translates words offline, saves them to your own tagged word list and helps you review them with flashcards.

Since 2025

Courses and learning · Individuals and families

0

Practise a new language by chatting with AI, tapping words to save them and reviewing them later with spaced repetition.

Since 2025

Free plan · Courses and learning · Individuals and families

0

A federated code host with stacked pull request review and CI. You can use the hosted service or run it yourself.

Since 2025

Developer tools · Developers

0

Independent hosted git service with merge requests, CI runners, a container registry and AI code review for dev teams.

Since 2026

Free plan · Developer tools · Developers

0

Records program execution so developers can replay and step back through bugs in the IDE, CI and code review.

Since 2025

Free plan · Developer tools · Developers

0

A browser extension for Chinese learners that puts words from your level into English pages, with readings and meanings on hover.

Since 2026

Courses and learning · Individuals and families

0

Phone app for learning a language by listening to native podcasts with synced transcripts and tap-to-translate words.

Since 2025

Subscription · Courses and learning · Individuals and families

0

A reading app for language learners that imports books, articles and videos, translates words and sends vocabulary to Anki.

Since 2026

Free · Courses and learning · Individuals and families

0

Lets teams write UI tests for iOS, Android and web apps as short YAML scripts, run them free locally or pay to run them in the cloud.

Free plan · Developer tools · Developers

0

Graded Japanese stories at your JLPT level, with tap-to-define words, grammar notes, audio and flashcards.

Since 2026

Subscription · Courses and learning · Individuals and families

0

A Chrome extension that translates X and Reddit posts and quizzes you on new words, for people learning English.

Since 2026

Subscription · Courses and learning · Individuals and families

0

Records every AI agent decision in a signed, tamper-evident log so teams can show regulators what their AI did under the EU AI Act.

Since 2026

Free plan · Developer tools · Developers

0

Translates words and short phrases with examples and pronunciation, then saves them to a personal list for language learners.

Since 2026

Courses and learning · Individuals and families

0

A local desktop editor for writing language courses with lessons and self-marking exercises, plus a free app to study them.

Since 2026

Free · Courses and learning · Creators and writers

0

Tracks how much RAM and flash firmware uses on every commit and fails CI builds that go over set budgets.

Since 2025

Developer tools · Developers

0

Learn Japanese or Korean by tapping words in YouTube videos, manga and books, with flashcards that track what you know.

Since 2025

Free plan · Courses and learning · Individuals and families

0

Run an Android APK on a real ARM64 cloud device from the browser, or connect your Appium tests to it from CI.

Since 2026

Free plan · Developer tools · Developers

0

Short Spanish stories pitched at the words an A2 to B1 learner already knows, with unknown words brought back for review.

Since 2026

Free plan · Courses and learning · Individuals and families

0

An app for practising spoken conversations in 10 languages with an AI partner, then chatting with native speakers with translation.

Since 2026

Free plan · Courses and learning · Individuals and families

0

Learn to read Arabic with alphabet lessons, graded stories and flashcards that schedule reviews around your memory.

Since 2026

Free plan · Courses and learning · Individuals and families

0

Live voice lessons with an AI language tutor that corrects mistakes as you speak and remembers your past sessions.

Since 2026

Free trial · Courses and learning · Individuals and families

0

Throwaway test inboxes that pull out one-time codes and magic links, so developers can test login emails in CI.

Since 2026

Free plan · Developer tools · Developers

0

A language app where a partner or friend fills in words, audio and sentences for you to study, on iPhone and Android.

Since 2025

Courses and learning · Individuals and families

0

Language learners listen to free public domain audiobooks while following highlighted text and optional translations.

Free · Courses and learning · Individuals and families

0

Makes subtitles for your video and audio files so language learners can look up words and send them to Anki.

Since 2026

One-off payment · Courses and learning · Individuals and families

0

Learn any of 75 or more languages from almost any starting language, including rare ones, with a school option too.

Free plan · Courses and learning · Individuals and families