I have been using the language learning platform duolingo for quite some time now (I believe since shortly before it left beta, but this turns out to be difficult to check). Initially I was learning French, though I have since switched to Spanish for personal reasons that have nothing to do with duolingo. And it has actually been rather effective: I am not yet conversational, but I can see the parts that I am missing, and it is not far away. All of my usage was through the web interface until smartphoneification (September), when it moved to mostly the Android appliance for reasons of convenience. Most of the things I have to say about it are good, and I think on the balance I would encourage people to use it. I have one major complaint, however.
If one loads the duolingo home page, next to a stylized globe are the words "Learn a language for free. Forever.". And that's fine as far as it goes; the broke college student still in me appreciates the gesture of this knowledge platform not being restricted based on financial capability. The problem comes, in my estimation, from duolingo being a for-profit company.
And inevitably, since this is about an internet business that has promised a free product to its users, there are ads now. To their credit, duolingo has tried several other approaches to turning a profit, but they seem to have not stuck, given where we are now.
The ads seem to be in mobile only, which strikes me as bizarre and problematic. (I did test this without an ad blocker enabled.) Back when I started using the phone application in September, I almost never saw ads. Now, I see them after every section, which says that duolingo is getting desperate. This entertains me after their original claims that duolingo as a nonprofit "wouldn't be sustainable". Let us here also ignore how well Wikipedia is doing for itself.
Though I have not verified this myself due to lack of a spare $700, Wikipedia currently claims that these ads are Android only. I shouldn't need to explain why this is disgusting.
Weirdly enough, most of these ads (both in Spanish and English when I change my phone's language back and forth) are for tools to learn languages quickly. I fail to understand why these kinds of ads are permitted at all, since they are quite simply the competition. Perhaps they couldn't find any other buyers?
Taking a step back, I take issue with platforms that claim to be about education containing advertising of any kind. Education of this kind works by setting up an oracle, an all-knowing teacher, as the deliverer of content (in this case, it gets personified by a green owl). When the teacher delivers both knowledge and advertising, not only does it lie to the students by presenting paid sponsorship in the same way as factual information, but it also reduces the confidence the students can have in the teacher. This isn't a discussion-based course, or a Socratic questioning game, or anything like that; what is being presented here is statements that we know to be correct about how languages work.
And to back up even further, I take issue with advertising as a concept. The idea that, in an era where not only is the Yellow Pages an outmoded concept but we have had quality search engines (plural) for quite some time, people have trouble finding the things they are looking for. Ads pollute the landscape, physical and virtual, taking money from those who have it to convince regular people to buy things (products, ideas, etc.) they would not have otherwise, generally for problems that do not exist.
I avoid advertising through use of technology designed to remove them, and avoiding media in which they are unavoidable. But in this way I am privileged; most cannot go this route.
In the course of testing where the ads occurred on duolingo, I went back to the web interface for a day's practice. And I performed substantially worse than I do when practicing on mobile, from which I conclude that the mobile interface is not teaching as effectively. I have not decided what to do with this information yet.