We make one of these, so read this with the appropriate suspicion. What we can offer in return is a comparison that names what Duolingo is genuinely better at — and there is quite a lot — because a page that cannot do that is an advertisement, and you would be right to close it.
The short version
Duolingo is better at getting you to start and keep going. Its free tier is a complete course, it is on every platform, it covers forty languages, and it is the most effective habit-forming product the category has ever produced. If you have never studied a language and are not sure you will stick with it, it is a sensible first move.
Arbor is better once you actually need to speak to particular people about your particular life — a job, a partner's family, a move, a deadline you have given yourself. It is iOS only for now, and it currently has two complete languages against Duolingo's forty.
These are different tools. A lot of people would be well served by using Duolingo first and moving when it stops producing progress.
What Duolingo does better
- Its free tier goes further. Arbor has one too, but Duolingo's is a complete course you can finish without paying, and that is a real advantage rather than a technicality.
- Forty languages. We have two, with five more in preparation. If you want Navajo or Hawaiian, this is not a real choice.
- Habit formation. Whatever you think of streaks, they work on a great many people. Arbor deliberately does not use them, and we accept that this costs us some retention.
- Reading and listening comprehension. High-volume recognition practice really does build these, and Duolingo does an enormous amount of it.
- Every platform. Web, Android, iOS. Arbor is iOS only for now.
What Duolingo is not built to do
None of this is a flaw. It follows from serving five hundred million people with one curriculum.
The sentences are the same for everyone
They have to be. One course serves a nurse, a retiree, a student and an engineer, and the sentences that serve all four are the ones that serve none of them especially well. So you learn that the bear drinks beer, and you do not learn how to ask someone to swap your shift.
This matters more than it sounds, because memory is not neutral about content. Words attached to your actual Tuesday survive; words attached to nothing decay at exactly the rate you would expect.
Most exercises ask you to recognise, not produce
Tapping the right option from four is a different skill from pulling a word out of your own head with nothing to prompt you. It is why so many people with very long streaks freeze in a shop — the full explanation is here.
The streak measures attendance
A 700-day streak certifies that you opened an app on 700 days. It was never designed to certify that you can hold a conversation, and it does not.
Side by side
| Duolingo | Arbor | |
|---|---|---|
| Free tier | Yes — the whole course | Yes — daily limits |
| Languages | ~40 | Spanish, Polish · 5 more coming |
| Platforms | iOS, Android, web | iOS |
| Lesson content | Identical for every learner | Built from your life and goals |
| Main exercise | Recognition, multiple choice | Recall and speaking |
| Speaking | Short set phrases | Open conversation that remembers you |
| Review | Built into lessons | Per-word scheduling, from your own conversations |
| Level | Progress through units | Inferred from four measured dimensions |
| Motivation | Streaks, leagues, reminders | No streaks, no notifications that scold |
Who should use which
Stay with Duolingo if…
- You are just starting and want to find out whether you enjoy this.
- You want a language we do not have.
- You are not on iOS.
- You want to go as far as possible without paying anything at all.
Arbor is the better fit if…
- You have a specific reason — a job, a partner's family, a move — and a rough deadline.
- You can already recognise a lot and freeze when you have to speak.
- You want the words you learn to be the words you will actually say this week.
- Streaks and notifications make you feel worse rather than better.
What we will not claim
We have no independent study showing Arbor beats Duolingo. Nobody has run one, and any company claiming a specific multiple of faster learning is quoting their own marketing. What we can say is which mechanisms the research supports — retrieval over recognition, spaced review, speaking under mild time pressure, and material connected to your own life — and that Arbor is built around those four and Duolingo is built around a different set of priorities that serve a much larger audience.
Judge it yourself: have a thirty-second conversation with one of the tutors without signing up for anything.
Arbor builds this into the app.
Every lesson, conversation and review session is made from your own job, your own week and the people you are learning for. Spanish and Polish are ready today.