CertBrain, our study app for the AWS Certified AI Practitioner (AIF-C01) exam, is now on Google Play. Its courses were already on the web at certbrain.app; now they’re on your phone too. Sign in with the same Google account on both and your progress is the same in each.
It’s the third app built from one mobile codebase, after Braineos and Finance Brain. The second took real work to make the app work for more than one product. The third was mostly configuration, plus one feature CertBrain needed that the others didn’t.
What’s in the app
CertBrain follows the exam’s own structure, with one course for each of its five domains. In the app you get:
- Short lessons, each followed by a quiz of original scenario questions, with an explanation for every answer
- Spaced-repetition reviews, so each question comes back just before you’d forget it
- Your progress through each course, what to study next, and a daily streak
- A readiness diagnostic you can take straight from the sign-in screen, without an account
The third app was mostly configuration
When we added Finance Brain, we split the app into two layers. The build settings say which app this is: its name, package ID, link scheme, icons, version number, build project and Play upload key. A site profile inside the app holds everything else: the copy, colours, and which features exist.
For CertBrain, that meant one new entry in each:
- A build entry for
com.certbrain.app, with its own icon, build project and upload key. - A site profile with CertBrain’s colours and wording, and its features switched on or off. Courses and lessons are on. Making your own decks, browsing other people’s, voting and following are off, so the app doesn’t show them and the store listing doesn’t mention them.
Before submitting, we went through every screen against CertBrain’s real content: sign-in, Home, courses, lessons, quizzes and profile. None of them needed any CertBrain-specific code. The screens we built for Finance Brain already led with courses whenever a site has courses but no user-made decks, and CertBrain is exactly that kind of site.
The one new feature: a diagnostic before sign-in
On certbrain.app, the first thing we suggest is the readiness diagnostic: a short quiz across all five exam domains that shows where you’re strong and what to study first. It doesn’t need an account.
The app, though, asked you to sign in before showing anything. So we added:
- A public screen outside the sign-in gate, reached by a “Try the free diagnostic” button on the sign-in screen.
- A switch in the site profile. Only sites that have a diagnostic show the button, so the Braineos and Finance Brain apps don’t change.
- Questions from the server. The app doesn’t hard-code how many questions there are, so the website and the app always ask the same set.
- Scoring on the phone. Your answers aren’t sent anywhere. The results screen shows how you did in each domain, highlights the weakest one, and explains every question you missed.
The scoring logic is a port of the website’s, with its tests ported too, so both versions count the same answers the same way.
Saying what it isn’t
CertBrain helps people prepare for an AWS exam, but it isn’t an AWS product. The app says so on every course and lesson page, in the same words as the website and the store listing. That sentence lives in the site profile rather than in a screen, so there’s one place to change it.
Get CertBrain on Google Play, or take the diagnostic on the web to see where you stand.
CertBrain is an independent study resource. It isn’t affiliated with or endorsed by Amazon Web Services.