What research supports — and how far the claims can go
Research supports general learning principles under many conditions. APE has not published its own randomized controlled trial.
Section 1
Retrieval and retention
Memory testing can improve delayed retention compared with repeated rereading under studied conditions.
Section 2
Distributed practice
Spacing generally supports durable retention, but optimal intervals vary.
Section 3
Transfer
Transfer effects exist but depend on the distance between practice and target task.
Section 4
How APE relates
- Hidden answers and writing create retrieval opportunities.
- Multiple choice supports recognition.
- Favorites and difficult-item tools create return paths.
- Glossaries and layers organize context.
Section 5
What Preply social proof means
It documents professional teaching experience and public reputation. It does not isolate the effect of APE.
Section 6
Limits
- No published APE randomized trial.
- No public effect-size estimate.
- Usage metrics are not long-term learning.
- Negative findings must also be documented.
Research references
These publications study general learning principles and did not directly evaluate APE.
- Roediger, H. L. III; Karpicke, J. D. (2006). Test-Enhanced Learning: Taking Memory Tests Improves Long-Term Retention. Psychological Science, 17(3), 249–255. DOI: 10.1111/j.1467-9280.2006.01693.x
- Karpicke, J. D.; Roediger, H. L. III (2008). The Critical Importance of Retrieval for Learning. Science, 319(5865), 966–968. DOI: 10.1126/science.1152408
- Cepeda, N. J.; Pashler, H.; Vul, E.; Wixted, J. T.; Rohrer, D. (2006). Distributed Practice in Verbal Recall Tasks: A Review and Quantitative Synthesis. Psychological Bulletin, 132(3), 354–380. DOI: 10.1037/0033-2909.132.3.354
- Butler, A. C. (2010). Repeated Testing Produces Superior Transfer of Learning Relative to Repeated Studying. Journal of Experimental Psychology: Learning, Memory, and Cognition, 36(5), 1118–1133. DOI: 10.1037/a0019902
- Dunlosky, J.; Rawson, K. A.; Marsh, E. J.; Nathan, M. J.; Willingham, D. T. (2013). Improving Students’ Learning With Effective Learning Techniques. Psychological Science in the Public Interest, 14(1), 4–58. DOI: 10.1177/1529100612453266
- Pan, S. C.; Rickard, T. C. (2018). Transfer of Test-Enhanced Learning: Meta-Analytic Review and Synthesis. Psychological Bulletin, 144(7), 710–756. DOI: 10.1037/bul0000151
Authorship and professional context
Pedro Luis — Creator of APE — App Piteco
Pedro Luis is a Brazilian English tutor and the creator of APE. His public Preply profile documents more than 1,900 lessons taught and a verified teaching certificate. These credentials describe the creator, not a scientific rating of the software.
Verify the public Preply profile
Last reviewed: 2026-07-25.