blas. vs Duolingo for Irish: What's Actually Different

If you're learning Irish, you've almost certainly tried Duolingo. It's free, it's everywhere, and it's the default starting point for most people. blas. is a newer app built specifically for Irish and Welsh. This post compares the two honestly: what each does well, where each falls short, and who should use which.

If you want more context on Duolingo's Irish course specifically, see Learning Irish on Duolingo? Here's What You're Missing. . For a broader look at every Irish learning app, see the Best Apps to Learn Irish in 2026 comparison.

Grammar Teaching

This is the biggest difference between the two apps and it shapes everything else.

Duolingo teaches grammar implicitly. You translate sentences and infer patterns from examples. There are no grammar explanations in the exercises. The old "Tips & Notes" sections were removed when Duolingo redesigned its course format. You can pick up basic patterns this way, but Irish grammar has enough complexity (two verbs "to be," VSO word order, prepositional pronouns, broad vs slender consonant rules) that guessing from context only gets you so far.

blas. teaches grammar explicitly. Each topic has a structured lesson that explains the rule, shows examples, and then drills it. You learn why Tá mé tuirseach uses tá but Is múinteoir mé uses is, not just that they're different sentences.

For a deeper look at what Irish grammar involves, see the Irish Grammar for Beginners guide.

Mutation Drilling

Duolingo introduces mutations as they appear in sentences. You'll encounter mo chat and a gcat but the app never explains why cat changed, which triggers cause which mutation, or what the full pattern is. Mutations are arguably the single hardest thing about Irish, and learning them by osmosis is extremely slow.

blas. treats mutations as a core skill. There are dedicated mutation sessions that drill séimhiú (lenition) and urú (eclipsis) systematically: every trigger, every consonant change, with spaced repetition scheduling so you revisit the ones you get wrong. The complete guide to Irish mutations covers what's involved.

Reading Content

Duolingo has no graded reading. The longest text you'll encounter is a single sentence.

blas. includes graded reading passages from A1 to C1. These are multi-paragraph texts with comprehension questions, designed to build reading fluency progressively. Reading is one of the fastest ways to expand your passive vocabulary and internalise grammatical patterns, and it's completely absent from Duolingo.

Conversation and Speaking

Duolingo has no Irish conversation feature. There are some listening exercises where you match audio to text, but no free-form speaking practice.

blas. has an AI conversation feature that lets you practise Irish in text-based dialogues with grammar feedback. It's not the same as speaking with a human, but it fills the gap between passive learning and real conversation.

Neither app replaces actual speaking with a person. If speaking is your priority, consider adding Pimsleur or SaySomethingInIrish alongside either app.

Vocabulary Approach

Duolingo teaches vocabulary through translation and matching exercises. Words appear in themed units and are revisited through the app's spaced repetition system. This works. Duolingo is genuinely good at getting you to remember words.

blas. teaches vocabulary in grammatical context. Words are introduced alongside the grammar patterns they appear in, so you learn not just what a word means but how it behaves: does it trigger mutation? What gender is it? How does it change in different cases? Both approaches have merit; Duolingo's is more immediately satisfying, blas.'s builds deeper understanding.

Spaced Repetition

Duolingo uses a proprietary spaced repetition system (Birdbrain). It schedules reviews, but you have limited control over timing and the algorithm prioritises keeping you in the app daily rather than optimal memory scheduling.

blas. uses FSRS (Free Spaced Repetition Scheduler), the same algorithm available in modern Anki. FSRS is research-backed and optimises for long-term retention. Each review is scheduled based on your performance history for that specific item.

Pricing

Duolingo: Free with ads. Duolingo Super (ad-free, unlimited hearts): ~€8/month.

blas.: Free tier covers the first two stages of grammar and mutations with unlimited sessions and full spaced repetition. Premium unlocks all content including advanced grammar, graded reading, AI conversation, writing, and exam prep.

On pure cost, Duolingo wins. The full Irish course is free. But the free tier on blas. covers more grammar depth than Duolingo's entire course does, just within a narrower scope.

Side-by-Side Comparison

Who Should Use Duolingo

Duolingo is the right choice if you're a complete beginner who wants a free, zero-friction way to start. The gamification genuinely helps build a daily habit. If you've never studied Irish and just want to dip your toes in, Duolingo is a perfectly reasonable place to begin.

It's also the right choice if gamification is what keeps you motivated. Streaks, leagues, and XP are powerful habit tools. If removing them means you stop studying, they're worth more than the pedagogical features they lack.

Who Should Use blas.

blas. is the better choice if you want to actually understand Irish grammar, not just memorise sentences. It's built for learners who want to know why things work the way they do: why mo causes lenition, why the verb comes first, when to use the copula.

It's also the right tool if you've outgrown Duolingo and feel stuck around A2. The mutation drilling alone covers ground that no other app touches. And if you studied Irish in school and are coming back, the placement test lets you skip past what you remember and focus on what you actually need.

Using Both Together

Many learners use both, and it's a reasonable approach, especially if you're early in your journey. A common pattern: Duolingo for the daily streak and vocabulary habit (5 minutes), blas. for focused grammar and mutation sessions (10-15 minutes). As you progress past A2, most learners find they rely on blas. more and Duolingo less.

Neither app covers everything. For speaking practice, add Pimsleur or SaySomethingInIrish. For immersion, try TG4 and Irish-language podcasts. No single app will make you fluent, but the right combination of tools gets you much further than any one alone.

The Honest Answer

Duolingo is a good starting point. blas. is a better learning tool. Duolingo will give you vocabulary and a daily habit. blas. will give you grammar, mutations, reading, and the understanding needed to actually progress beyond beginner level.

If you can only pick one: pick Duolingo if you're a true beginner who needs zero friction. Pick blas. if you want to move past A2, if you need to understand grammar and mutations, or if you studied Irish before and want to come back to it seriously.