Duolingo has been the go-to recommendation for Japanese learning for years. With its gamified lessons and recognisable green owl, it's introduced millions to Japanese basics. But recent controversies and fundamental limitations in its Japanese teaching methodology raise important questions about its future effectiveness.

Meanwhile, newer apps like Kann are offering targeted alternatives that address specific weaknesses in popular platforms. Here's an honest comparison of where each stands in 2025, including recent developments that Japanese learners should consider.

The Giant vs. The Specialist

Duolingo: The Mainstream Pioneer

Duolingo revolutionised language learning by making it free, gamified, and accessible to everyone. In 2024, English was again the most popular language studied around the world. It earned the #1 spot in more countries (135) than ever before, up more than 10% compared to last year. Its Japanese course has been one of the most requested and popular on the platform.

Duolingo's Approach:

• Gamified learning with streaks, XP, and leaderboards

• Translation-heavy exercises (Japanese ↔ English)

• Inference-based grammar learning

• Multi-choice questions with word banks

• Free access to core content

Kann: The Intermediate-Focused Alternative

Kann is built for intermediate & advanced learners who want to level up their specific interests through curated, practical vocabulary organised by frequency and specialised topics.

Kann's Approach:

• Topic-specific dictionaries for specialised vocabulary (Business, Anime, Technology, etc.)

• Frequency-based progression (1K, 2K, 3K most common words)

• Multiple question types including conjugation practice

• JLPT-organised kanji for systematic advancement

• Recognition-focused methodology for practical reading skills

The AI Controversy: A Game-Changer for 2025

Duolingo's AI-First Pivot

Recent developments have significantly changed Duolingo's landscape. Duolingo CEO wrote in an email to employees that disclosed the company plans to replace most human contract workers with AI and was highlighting its 148 new AI-created courses.

The implications are significant:

Content Quality Concerns: Former contractors report quality issues in courses that have shifted to AI generation.

The Scale vs. Quality Trade-off: "This launch reflects the incredible impact of our AI and automation investments, which have allowed us to scale at unprecedented speed and quality," - the CEO. However, We'd rather move with urgency and take occasional small hits on quality than move slowly and miss the moment, suggesting Duolingo is prioritising speed over content accuracy.

User Reaction: Folks online have found the language app's shift towards AI pretty bad, especially because Duolingo has been using AI for years now. "The best time to delete Duolingo was when they first included AI shit," one user quipped. "The second best time is now."

Kann's Human-Curated Approach

Kann represents the opposite philosophy, every word and question is curated by myself who understand Japanese learning methodology. This becomes increasingly valuable as AI-generated content proliferates across language learning platforms.

Japanese Learning Effectiveness: The Core Issues

Duolingo's Fundamental Problems for Japanese

The effectiveness issues with Duolingo's Japanese course aren't new, but they're becoming more pronounced:

Grammar Explanation Deficit: The platform is brilliant at keeping you motivated and engaged throughout the lessons, however for serious language learners we found it to be seriously lacking in basic grammar and speaking practice.

Translation-Heavy Approach: Duolingo's exercises present certain limitations when it comes to effectively learning Japanese. The translation exercises, both from Japanese to English and vice versa, do not Align with real-world language use.

Limited Practical Application: While I feel like the program could use more grammar instruction, I kind of like figuring it out for myself by parsing out sentences. Duolingo feels designed to give you those "aha!" moments when something finally clicks. However, this approach leads to gaps: I do worry that if I continue making assumptions based on parsing out sentences, I'm going to make some wrong assumptions that will become ingrained.

Kann's Targeted Solutions

Kann directly addresses these issues:

• Systematic kanji progression through JLPT levels rather than random exposure

• Multiple question types that test understanding from different angles

• Frequency-based vocabulary that prioritises practically useful words

• Topic-specific learning for immediate real-world application

User Experience Reality Check

Duolingo: Gamification vs. Learning

The Motivation Trap: Right now, I'm in the semifinals of the Diamond Tournament. When I last stopped using Duolingo, they had just introduced the league system. When I started learning Japanese, I didn't care too much about progressing in the leagues. However, my motivation to learn the language gave me plenty of XP to easily reach Diamond League. Now, as I'm getting deeper into Japanese and the lesson are getting harder, I'm struggling to keep up.

Real-World Results: However, in retrospect, picking up the language might have been more effective had we enrolled in hours-long intensive courses a couple weeks before the trip. After 400+ days of Duolingo study, users often find limited practical application.

Completion vs. Competency: The graph shows that Duolingo coverage is only about 15% the lexis for JLPT N1. Even completing the entire course provides limited Japanese proficiency.

Kann: Efficiency-Focused Design

Kann's users report immediate practical value from topic-specific vocabulary and clear progression through frequency-based content. The generous free tier (8 months of content) allows thorough evaluation before any payment decisions.

The Content Quality Divide

Duolingo: AI-Generated vs. Human-Curated

The New Reality: Language app Duolingo announced on Wednesday that the company was doubling its language courses offering by adding 148 new ones, all made with generative AI. This rapid expansion raises questions about quality control and cultural accuracy in Japanese content.

Limited Effectiveness Research: One finding from the researchers was that the actual time savings from AI tools were far smaller than expected, with users reporting only a 2.8 percent reduction in work hours, which is raising the question of whether Duolingo is ultimately wasting its employees' time by pressuring them to adopt a tool with little real-world evidence of its promised benefits.

Kann: Human Curation

Every aspect of Kann is designed by human (still me) who understand Japanese learning challenges. This includes:

• Culturally appropriate topic dictionaries

• Professionally selected frequency-based vocabulary

• Multiple question types that reinforce different aspects of understanding

• JLPT-aligned progression that matches actual proficiency levels

Pricing and Value Considerations

Duolingo: Free with Limitations

• Free tier: Basic functionality with ads and limited features

• Super Duolingo: $7/month or $10/month for family plans

• Hidden costs: Time investment with questionable returns on Japanese proficiency

Kann: Transparent Value

• Generous free tier: 8 months of content including all JLPT kanji

• Unlimited limitation: Lives system that basically serve as a gateway to upsell

• Clear progression: €7/month, €70/year, or €200 lifetime

• Focused value: Every feature designed specifically for Japanese learning efficiency

The Trust Factor in 2025

Duolingo's Credibility Questions

The AI controversy has raised broader questions about Duolingo's priorities:

At one point, I held a 1981-day streak in the paid version of Duolingo. I just couldn't deal with the ads and restrictions of the free version… I enjoyed the quirky language lessons. It was obvious that the people creating language lessons were having fun with it. AI, though, regurgitates a lot of bland, watered-down, derivative copy. I'm skeptical about how hands-off Duolingo can go with its shift toward AI without losing its spunk and soul.

Kann: Human-Centred Philosophy

Kann's approach reflects a commitment to human expertise in language learning design. This becomes increasingly valuable as the market floods with AI-generated content of questionable quality.

When Each Makes Sense in 2025

Choose Duolingo if you:

• Are a complete beginner who needs basic Japanese introduction

• Want completely free access and don't mind significant limitations

• Enjoy heavy gamification and social competition features

• Need motivation to start your Japanese learning journey

• Don't mind supplementing with multiple other resources for real progress

• Aren't concerned about AI-generated content quality

• Haven't yet reached intermediate level where specialised vocabulary matters

Choose Kann if you:

• Have intermediate Japanese knowledge and want specialised vocabulary

• Want to level up specific interests (business, anime, technology, etc.)

• Prefer human-curated content designed by Japanese learning human

• Need efficient vocabulary building beyond basic conversation

• Value systematic JLPT progression for advanced kanji

• Want substantial intermediate content without quality compromises

• Are concerned about supporting platforms that replace human expertise with AI

• Have moved beyond beginner apps and need targeted advancement

The Bottom Line for 2025

Duolingo's position has weakened significantly due to both longstanding pedagogical issues with its Japanese course and recent concerns about AI-generated content quality. The company's shift toward AI-first development raises questions about future content reliability.

Kann serves the market Duolingo can't reach, intermediate and advanced learners who need specialised vocabulary beyond basic conversation. While Duolingo might introduce you to Japanese, Kann helps you master the vocabulary for your specific interests and professional goals.

The fundamental question isn't just about effectiveness, it's about values and level. Do you want basic introduction with AI-generated content, or specialised advancement with human-curated expertise? Do you want to learn generic phrases, or master vocabulary for business, technology, anime, or other specific interests?

For intermediate Japanese learners in 2025, Kann's human-curated, specialisation-focused approach offers both better advancement opportunities and alignment with supporting quality language resources.

The choice is clear: While Duolingo may remain adequate for casual experimentation, learners serious about Japanese proficiency deserve tools designed by humans who understand the language's unique challenges.

Try Kann to experience human-curated Japanese learning designed for practical results. With 8 months of free content including all JLPT kanji, you can evaluate the difference without commitment, just like Japanese learning should be.