The language learning app market has exploded. Between gamified self-study apps, AI-powered conversation tools, and live tutor platforms, the options are overwhelming — and the marketing promises are almost always exaggerated. 'Fluent in 3 months' has become a cliché of the industry.
We spent six months testing three of the most talked-about platforms — Mondly, Duolingo, and Novakid — with real learners at different starting levels. Here is what we found.
The Platforms at a Glance
| Feature | Mondly | Duolingo | Novakid |
|---|---|---|---|
| Teaching model | App-based (AI + AR) | App-based (gamified) | Live online tutors |
| Languages available | 41 | 40 | English only |
| Suitable age | Adults & teens | All ages | Ages 4–12 |
| Free tier | Yes (limited) | Yes (full, with ads) | Trial lesson only |
| AI conversation | Yes (chatbot + AR) | Limited (basic chat) | Human tutors |
| CEFR alignment | A1–B2 | A1–B1 (approx.) | A1–B2 |
| Price/month | ~£7–10 | Free / £7 Plus | ~£65–80 |
Mondly: Best for Adults Who Want Structure
Mondly occupies an interesting middle ground: it's an app-based learner like Duolingo, but it takes a more structured, pedagogically serious approach. Lessons are built around real-world conversational scenarios — ordering food, checking into a hotel, making appointments — rather than abstract vocabulary lists.
The standout feature is Mondly's AI chatbot, which simulates realistic conversation in your target language. You speak (or type) and the AI responds contextually, coaching your pronunciation and correcting grammar errors. The Augmented Reality feature is a gimmick in practice, but the core conversational AI is genuinely useful.
Pros
- Real-world conversational focus from day one
- AR and AI chatbot features are genuinely engaging
- Covers 41 languages including less common ones
- Structured curriculum with clear progression
- Affordable — often 50–70% off annual plans
- Available on web, iOS, and Android
Cons
- Free tier is very limited (one lesson per day)
- Speaking recognition not always accurate for complex sentences
- Less social/community features than Duolingo
- Does not take learners to advanced (C1+) levels
Duolingo: Best Free Starting Point
Duolingo's genius is that it is completely free and deeply gamified. The streak system, achievement badges, and social leaderboards make it one of the most habit-forming apps ever created — and for absolute beginners who have never opened a textbook, it is genuinely effective at building a vocabulary foundation.
The honest limitation: Duolingo's exercises are too heavily focused on reading and writing, with insufficient speaking and listening practice. After a year of daily Duolingo, most users have strong recognition vocabulary but struggle with real-world conversation. It is a starter, not a full course.
Pros
- Completely free with full functionality (with ads)
- Habit-forming gamification is best-in-class
- Perfect for absolute beginners
- 40+ languages available
- Large community with lots of social features
- Short lessons work well for busy schedules
Cons
- Does not develop real conversational fluency
- Vocabulary taught without sufficient context
- Grammar explanation is minimal
- Tops out at approximately A2–B1 level realistically
- Duolingo Plus removes ads but adds limited academic value
Novakid: Best for Children
Novakid is a completely different kind of product: it is a live, online English tutoring platform for children aged 4–12, not a self-study app. Each lesson is a 25-minute video call with a qualified English teacher, built around games, stories, and interactive activities designed specifically for young learners.
The results parents report are impressive. Unlike app-based learning, children receive immediate, personalised feedback from a real human — which is how children actually develop language competency. The platform supports Beginner to B2 level (Cambridge English aligned), and the teachers are trained specifically in young learner methodology.
Pros
- Real human teachers specialised in teaching children
- Lessons are genuinely fun and engaging for kids
- Flexible scheduling — book lessons at any time
- Cambridge English aligned curriculum
- Progress reports and homework to supplement live lessons
- Free trial lesson available
Cons
- Significantly more expensive than app-based alternatives
- English-only (not suitable for adults or other languages)
- Requires a stable internet connection and device with camera
- Quality can vary slightly between individual teachers
Which Platform Should You Choose?
- Complete beginner adult learner, tight budget → Start with Duolingo (free) to build a base, then upgrade to Mondly for conversation practice.
- Adult learner who wants structured progress → Mondly, particularly on an annual plan with a discount code.
- Child aged 4–12 learning English → Novakid is in a different category entirely and the most effective option for this use case.
- Learning a language for travel → Mondly's scenario-based lessons are specifically designed for this.
- Just want to maintain a language you already know → Duolingo's daily habits are perfect for maintenance.
Mondly runs substantial discounts (50–70% off) during promotional periods. Check our Education Deals page for the latest active promo codes before subscribing — annual plans in particular can work out under £3/month with a discount.
Final Verdict
There is no single winner here because these platforms serve different learners. Duolingo is the best starting point if cost is a concern and you are an adult absolute beginner. Mondly is the best all-round paid app for adults who want real conversational progress. And Novakid is simply the best platform for children learning English — there is no app-based equivalent for that age group and use case.