For adults wanting to learn a new language, the range of ways to learn has never been wider. Self-learning apps offer flexibility, low cost, and independence. One-on-one tutoring offers sustained interaction with another person. Both have a place, and many learners try one before the other, but few studies follow the same learner through both. What changes when someone who has spent months with an app begins working with a tutor instead?
Preply helps people on their language learning journeys by connecting them with real tutors who provide personalized one-on-one learning experiences online. In 2026, Leanlab Education, an R&D lab, partnered with Preply, a global language learning platform, to answer that question.
In the spring of 2026, Leanlab studied how one-on-one tutoring impacts learners who had previously used a leading self-learning language app. A subset of native Spanish speakers from the related fall 2025 app study agreed to participate in a 12-week follow-up study using Preply, working toward their professional goals with a tutor. Having experienced both approaches in sequence, these learners were well positioned for comparison.
The Research
Leanlab followed 113 native Spanish speakers between the ages of 25 and 50, all learning English to achieve professional goals. Over 12 weeks, participants completed an average of 23 Preply tutoring lesson hours. In the prior self-learning language app study, these same participants had engaged with the app for an average of 18 hours over the same period.
Data sources included surveys measuring learner perceptions, goal achievement, and likelihood to recommend, as well as an independent standardized language assessment administered before and after the 12-week period. Select information was compared from survey data collected from the same 113 participants during the prior self-learning language app study.
This sequential design allowed for within-person comparison of learner outcomes across the two approaches. As such, findings reflected learner perceptions and self-reported comparisons rather than causal evidence.
As an independent research partner, Leanlab brought expertise in codesign research and education technology evaluation to support study design and analysis, with the goal of producing independent findings that are both methodologically sound and useful for Preply and language learners evaluating available programs.
The Findings
Descriptive findings from this follow-up study suggested that personalized, human-led tutoring with Preply delivers meaningfully different outcomes than app-based self-learning — across motivation, speaking skills, goal achievement, and likelihood to recommend.
FLUENCY AND SPEAKING
100% of participants said Preply contributed more to their fluency than the leading self-learning app. Every single one.
Learners demonstrated statistically significant CEFR-level gains after 12 weeks in:
Speaking
Pronunciation
Reading
Learners also felt that Preply:
Contributed more to their speaking ability: 98% of learners.
Improved their speaking confidence more: 99% of learners.
MOTIVATION AND SUPPORT
9x as many learners said Preply was more motivating than the leading self-learning language app.
Learners also preferred Preply over the leading self-learning app across key drivers of motivation:
98% reported feeling more supported in making progress in English.
9 in 10 learners felt that their experience was more personalized.
76% of learners cited human connection as key to their learning experience.
GOAL ACHIEVEMENT
Goal achievement doubled with Preply. 56% of learners achieved their goals very well or completely, up from 27% with the self-learning app.
Learners also reported:
Faster progress: 99% felt they progressed faster, and nearly 7 in 10 felt they progressed much faster.
Greater contribution to real-world English use: 93% said Preply was better for everyday communication, and 94% said it was better for professional English.
LIKELIHOOD TO RECOMMEND
7 in 10 learners would highly recommend Preply after just 12 weeks.
135% more learners would strongly recommend Preply: 80 learners vs. 34 for the self-learning app.
58% of those least likely to recommend the leading self-learning app became strong advocates for Preply*.
Looking Ahead
Preply and Leanlab Education are continuing their research partnership to explore additional questions about effective language learning. This ongoing work will deepen our understanding of how personalized tutoring can best serve language learners with different goals and initial skill levels.
To learn more about Leanlab Education's independent research services or to explore partnership opportunities, visit our Codesign Product Research webpage. To learn more about Preply's approach to language learning and the results of this study, visit their Proven Progress Platform webpage.
Notes on the assessment. Participants improved their CEFR test scores on average over 12 weeks. Assessment reflects pre- to post-Preply gains only; a change in assessment tools between studies prevented examination of English skill growth across both study periods. Statistically significant improvements in speaking, pronunciation, and reading were measured at ɑ = .05.
* 15 out of 26 participants.