Learn C#: an app for learning C# and .NET on your phone

On a phone, the things that decide whether you finish are lesson length, what happens when you hit a compiler error, and whether practice is more than tapping the right answer. Learn C# is built around those constraints: over 100 lessons of five to ten minutes, quizzes and coding challenges after every topic, and an AI Mentor that explains errors in plain English. It is free to start on iOS and Android, in 22 languages.

You can learn the language itself on a phone. Syntax, control flow, methods, object-oriented design and LINQ are ideas you can read, practise and be quizzed on in short sittings, and ten minutes a day beats an IDE you open twice a month. You will want Visual Studio or the .NET SDK on a computer once you are building multi-file projects or a Unity game, but that comes after the fundamentals, not before them.

.NET runs a large share of enterprise and backend software, and C# is the scripting language of Unity, so one syntax opens desktop apps, web backends, cloud services, games and mobile. It is modern, readable and strongly typed, which means the compiler catches mistakes early and pushes you into good habits from day one. As a first language chosen for employment rather than novelty, it remains a solid pick.

Unity scripting is done in C#, so the time you spend on variables, methods, classes and inheritance is time spent on Unity. Most people who bounce off game development tried to learn an engine and a language at the same time. Getting comfortable with the language first makes the engine's own tutorials read as familiar. Learn C# covers those fundamentals and the foundations for Unity game development, not the editor itself.

C# is the language — the syntax you write. .NET is the platform it runs on: the runtime that executes your compiled code, plus a standard library of ready-made types for strings, dates, collections and file access. You write C#, and .NET is what makes it run and what supplies most of the building blocks. Learning the language in practice means learning to use that library, which is why the two are taught together.

Consistency matters far more than total hours. With short daily sessions, most beginners are writing small console programs in the first week and are comfortable with classes, collections and error handling within a couple of months — well before anything counts as job-ready. Learn C# is shaped for exactly that: lessons of five to ten minutes, quizzes after each topic, and streaks, progress tracking and reminders so the gap between sessions does not grow.

The app is free to download on the App Store and Google Play. The first course is free, with a daily allowance of AI Mentor questions, so you can work through real lessons before deciding anything. Pro is the paid upgrade: it unlocks every course, removes ads and makes the AI Mentor unlimited. Nothing forces an upgrade in order to finish the free course.

Not fully, and it is better to know that first. The app is built for patchy conditions rather than for having no connection at all — lessons load fast and keep working on flaky connections, which covers most commuting. That is not an offline mode, and the AI Mentor in particular needs a connection because it answers your questions live. If a guaranteed offline app is what you need, this is not it.

Learn C# runs on iOS through the App Store and on Android through Google Play. The app itself is available in 22 languages, so the material is not English-only. It is rated 4+ for content, meaning there is nothing age-restricted in the lessons, and it is free to download on both stores with an optional Pro upgrade that unlocks every course.

Yes. Pass the final exam and the app issues a certificate of completion for the course. It is a completion certificate rather than an accredited qualification, so treat it as evidence of work done — worth listing on a CV next to the exercises and coding challenges you can actually talk through in an interview, rather than as a formal credential.