Happyexam: Class 10 Exam Prep

Inspiration

the app inspired from my sister, when she in class 10 he struggles to practice question for every chapter that reason we built Happexam

What it does

happyexam is education app that help class 10 students in Mathematics, Physics, Chemistry and more subjects. It helps the student by practise question by providing 100 to 200 questions for each chapter so students can clear his concept and boost his confidence. we provide notes with high precision quality notes so student can revise the concept before the exam. Built a solid content foundation: 5,000+ manually verified MCQs across 8 subjects for Class 10

How we built it

Happyexam publish in both platform android as well Web

Android we used react-native(expo) framework for creating apps and used redux and redux-persist for state management and storage the Ui of app is designed with nativewind library (RN tailwind) and used reanimated for smooth transition and animation. it used Ratex (a rust-based engine for rendering latex natively) for rendering math formula and latex

Web we used to react framework for creating web version and redux, redux-persist for state-management and storage. the Ui of web version is designed by tailwindcss, and used swiperjs for swiper animation and used motion for transition and button effect in web version we used Katex (created by khan academy) for math rendering because it too fasts and linked smoothly

Challenges we ran into

there are several problems faces to create this app.

1- rendering math formula in react-native, we know that natively we don't have any engine to render math formula or latex in react native. I researched and I found no solution, so I write WebView based solution.

Webview is used to render website in your app, so we send the value of math formula to WebView by postMessage function it render send back to react-native. because our app is also providing MCQ so we render 5 WebView at one time that make buggy and laggy. then we found Ratex

Ratex is rust based engine for rendering latex in web, flutter, react-native, android(native) natively no DOM, no WebView and it really game changer for me. I integrate this library and it solve the performance problem and many more.

2- Ratex just launched and have many problems like layouting the math formula, so I contribute on that library and fixed bugs as well

3- creating quality, flawless question in both Hindi and English language.

writing a question with high quality with absolute grammar is nightmare for me. we take help from ai, but he makes mistake, then we used some advanced model to solve that, and it really work but it also makes huge mistake. like not used katex, wrong answer, wrong option index, there are many more. we build own software to visualize everything and solve question, so we know everything works perfect.

4- Katex error problem in solution and question

we create 100-200 question per chapter in math, physics we used Katex for writing math formula, and writing Katex is also nightmare, even good ai model not fixed, so we write Katex for every math formula and symbol. we used same software to know that Katex render properly even sometime one chapter take 15 -16 hours to finished one chapter.

5- designing solution for every question Every question has solution and explanation and creating solution for every question is 2-3 times more tough than creating question and option because one single math problem can take 45 minutes because it is multistep solution, need precision Katex verify the solution is correct or not

6-translation error and misaligned option in Hindi and English we create this app for Hindi language students translating from English to Hindi it also a huge problem because translator don't translate perfect Hindi so for that I also test every line in question, option, solution.

Accomplishments that we're proud of

the app is published on play store and web and used by 50 user current time we created 22 chapters high precision notes by using obsidian software
we created high quality, flawless 5000+ MCQ questions and his solution

What we learned

Now I am expert on latex. now I understand why performance matter. why architecture. is matter because creating 5000+ question with such type of schema really hard. core level of react and react native redux persist and RTK-query advanced backend principle and system design

What's next for Happyexam: Class 10 Exam Prep

now we plan for adding more notes, flashcard, PYQ for including many state boards, adding leaderboard system as well. improvements in Ui and animation