splearn.io 2017 – 2019 View project page here
A screenshot of the splearn app on a tablet device 09:00 AM Fri Jan 1 90% Review Add Question How do you spell necessary? Answers: • necessary Behaviour: • Question will always be asked audibly • Spelling matters spelling Wie schreibt man Naturwissenschaften auf Deutsch? Answers: • naturwissenschaften Behaviour: • Question will always be asked audibly • Spelling matters german spelling Can you multiply matrices of shapes: [4, 3] and [2, 3]? Answers: • Yes math linear algebra Define seminal Answers: • strongly influencing future developments vocabulary Who discovered spaced repetition learning? Answers: • Hermann Ebbinghaus people What's the name of the counterintuitive problem, where changing you choice of door on a gameshow increases the odds in your favour? Answers: • Monthy hall • Monty hall problem • The monty hall problem maths What is the word for "any effect on a person, resulting from anyactivity of one or more otherpersons acting as healthcareprofessionals or promotingproducts or services asbeneficial to health, which doesnot support a goal of the personaffected. Answers: • Iatrogenesis vocabulary What does CSRF stand for? Answers: • Cross site request forgery security QA Pairs splearn.io Splearn

The problem

Trying to learn many things at once in an industry that is constantly changing is difficult.

A new JavaScript framework seems to be born every 6 months. If it doesn't, don't worry, a new architectural paradigm will probably take its place.

Remembering the new and the old can seem like a twisted game of whack-a-mole. At least for me.

Although existing solutions like Anki existed, they didn't meet my needs. Such as not bricking my laptop. I wanted to be able to ask different types of questions. Spelling questions should also never be presented visually but audibly only. On the other hand, questions where I didn't care how the answer was spelt should not test the spelling. Rather it should just kind of know if the answer I gave was correct.

Testing my knowledge should be doable offline so that the time with the train's spotty internet connection could be well used.

The solution

Let's tackle this problem by problem. First off, the most fundamental: how to remember what you learn.

The forgetting curve dictates that the more you review a fact, the slower you will forget it as depicted in the following chart.

Forgetting curve diagram 100% First seen Reviews 90% 80% 70% Chance of remembering Days 10 20 30 40 50 60 Example Forgetting Curve

So all we need to do is review it often? No. If you were to review something day after day, you would probably remember it well, but it wouldn't be that efficient. Far more efficient would be to review it just before you're about to forget it. Remember, the goal is to learn a lot. You can't do that if you have to remember the same things every day.

You might think that reviewing a topic 5 times on subsequent days will help you remember something just as well as reviewing a topic the same number of times on staggered days as is shown in the chart above. It's not. Multiple studies have shown that spacing out repeated encounters help you remember better in the long-term than with repetitions that are bunched together.[1]

Therefore, to help remember when to review the study matter at the most optimal times for retention, I built Splearn. Splearn (pronounced 'sp' — as in spoon and then 'learn') notes the last times you reviewed a question and whether you answered correctly or not. Based on this information, it uses an algorithm to calculate the next best time to review the material and will notify you accordingly.


  1. Kang, S. H. K. (2016) ‘Spaced Repetition Promotes Efficient and Effective Learning: Policy Implications for Instruction’, Policy Insights from the Behavioral and Brain Sciences, 3(1), pp. 12–19. doi: 10.1177/2372732215624708.