JUST twenty years ago, a language student removed from live practice or in-person classes had to rely on books or cassette tapes. Those were tough times: learners needed exceptional motivation, and got little feedback on their progress. Later on, websites providing textbook-style grammar lessons would pop up, making access easier but still giving little in the way of interaction. Starting in the mid-1990s, Rosetta Stone (whose latest incarnation Johnson reviewed in January) added a bit of interactivity to the learning process, if at steep prices. As software like Rosetta Stone’s improved and added more online functions, free and low-cost services started to appear to compete with it. Unlike older rote grammar websites, the best among these sites have focused on interaction and personalised feedback. Livemocha, for one, pairs far-flung learners on its forums and encourages users to trade languages. Livemocha and its 16m subscribers were swallowed up by Rosetta Stone in April, filling out Rosetta Stone’s once-vacant online forums.

For those who lack the patience for forums or the pockets for pricey services, there are (of course) apps for that. Two in particular stand out as excellent. The first is Duolingo, which I have been using to learn French for eight months now. The other is Babbel, where I’ve been picking at Dutch for the past two months.

Duolingo, unlike Rosetta Stone, Livemocha or Babbel, is free. (The company makes money by charging for text translations, crowdsourced from users. That corner of the site isn’t entirely smooth yet, so it’s a distraction for most learners.) Lessons are available for English, French, Spanish, German, Italian and Portuguese. Much of the learning happens in the form of rapid-fire quizzes, which switch frequently between testing speaking, listening, and writing. High scores unlock further lessons. You can compare your progress with your friends’ through Facebook, a successful use of "gamification". Duolingo’s free smartphone app offers nearly all the same content as the website, too. I was surprised at how good the app was, since most language apps have tended to be spartan, buggy or both. Duolingo’s speaking quizzes on the app seem particularly magical considering the voice recognition tech behind it was nearly unusable just a few years ago on other software.

It’s a joy to use Duolingo, in part because its phone app is not only convenient to use but full of new content. But while it’s a great start, it’s not perfect. For now, its lessons are deep—I haven’t even spotted the end-mark of my French lessons—but the language selection is small. I also suspect that Duolingo’s clientele is limited by its style of teaching. The quizzes focus on mastering structural blocks, like relative pronouns or a particular class of nouns. It doesn’t really teach conversational skills. If I didn’t already know the basics of French conversation, I’d be helpless in France. The focus is great for serious beginners or long-term learners, but much less useful for casual learners or tourists.

Babbel fills in some of those gaps. It isn’t free: it runs from $7.45 to $12.95 a month. This is still far cheaper than Rosetta Stone ($239 for an annual subscription, or $25 a month, with frequent sales and discounts). I needed a Dutch class before I left for the Netherlands, and Babbel stepped up with  one of the very few online Dutch courses out there.  In addition to the six languages also offered by Duolingo, Babbel has Swedish, Turkish, Dutch, Polish, Indonesian, Norwegian and Danish. They’re not all as well developed as Spanish or French, but many learners will be grateful that they exist at all.

Babbel’s lessons, unlike Duolingo’s, first focus on building basic conversational skills. For a Dutch learner like me, more interested in speaking than reading, Babbel works well. (I suspect that most learners are first interested in learning how to communicate, anyway.) Babbel will also occasionally set off immersive lessons by explaining grammatical concepts at length. As a linguistics enthusiast, I particularly enjoyed the little tutorials. It’s a nice contrast to the technique of, say, Rosetta Stone, which emphasises total immersion much more than rote grammar.

Babbel’s interface is clean but still a little buggy. It’s hard to repeat slides or audio recordings without going through an entire lesson twice. The microphone tech didn’t like my Dutch pronunciation (which could be entirely my fault), and repeating yourself six or seven times to get it just right is wearying. I suspected that the issues were limited to the still-new Dutch syllabus, but I found many of the same problems in the French section. Babbel’s phone apps (one for each language) are good, but not great. It works without an internet connection, a plus. It’s perfect for reviewing vocabulary. But it doesn’t offer all of the same functionality of the website (unlike Duolingo), a shame considering it’s a paid service. But Babbel's focus on speaking, the wide selection of langauges and the modest price make it competitive with both the free Duolingo and the sophisticated but pricey Rosetta Stone.

For students learning English, Spanish, French, Portuguese, German or Italian, Duolingo and Babbel might actually work quite well in concert, filling in the other’s gaps. I, for one, plan to continue using both. Duolingo and Babbel are two exceptionally good sites. Given that they’re competing quite vigorously with each other and with Rosetta Stone, their services can only get better. Language learners can expect some exciting developments in free and low-cost services in the next few years.