How to Test Your App Before Launch (Without Writing Tests)

Professional developers write automated tests — code that checks other code. That's valuable, and worth learning about later (Getting AI to Write Tests That Actually Catch Bugs). But before your first launch, the most effective thing you can do needs no code at all: use your app deliberately, like a careful stranger would.

Set aside an afternoon. Here's the plan.

Before you start

Test on the live (or preview) version, not just your own computer. Many bugs only appear once an app is deployed. (Why Does My App Work Locally but Not in Production?)
Use test accounts and test payment modes. Never experiment on real customers' data.
Open a notes file for bugs. For each: what you did, what you expected, what happened, and a screenshot. This is exactly what you'll give your AI tool later.
Keep the browser console open (right-click → Inspect → Console). Red errors appear there even when the page looks fine.

Part 1: the happy paths

Walk through every main journey, start to finish, as a brand-new user:

Sign up with a new email
Confirm the email (did it arrive? in spam?)
Log out, log back in
Reset your password — the whole flow
Do the main thing your app is for, end to end
Edit something, then delete something
If there are payments: pay (in test mode), check access was granted, cancel
Delete the account, if that's offered

If you planned your app with user journeys (How to Plan Your First App), use them as your script.

Part 2: try to break it

Real users do unexpected things. Do them first:

Forms

Submit every form empty
Enter very long text (paste a few paragraphs into a name field)
Use special characters: O'Brien, Zoë, emoji 🎉, <b>bold</b>
Enter wrong formats: letters in a number field, an invalid email
Click submit twice quickly — do you get two of everything?

Navigation

Use the browser Back button in the middle of a flow
Refresh the page halfway through something
Open the same page in two tabs and change things in both
Bookmark an inner page, log out, and open the bookmark

Conditions

A brand-new account with no data — do empty pages look sensible, or broken?
An account with lots of data — does anything get slow or overflow?
A slow connection — browser dev tools can simulate one (Network tab → throttling)
Phone screens — see Responsive Design Basics
A different browser — at least Chrome and Safari

Part 3: the security checks

These matter most and take fifteen minutes. Create two accounts, A and B, each with some data:

Logged in as A, can you see B's data by changing an ID in the address bar?
Logged in as A, can you edit or delete B's data?
Logged out, can you open private pages directly?
As a normal user, can you open admin pages directly?
View the page source and the browser's Network tab — are there any secret keys, or data you shouldn't see?

If any of these succeed, fix them before launch. Authentication vs Authorization explains why they happen, and the Security Checklist for Vibe-Coded Apps covers the rest.

Part 4: the launch details

Your domain works, with the padlock (HTTPS), with and without www
Emails arrive in the inbox, not spam, with links pointing to the real domain (How to Send Email From Your App Without Landing in Spam)
Payments in live mode work with a real card (then refund yourself)
A 404 page exists for mistyped URLs
The page title and preview look right when you share a link in a messaging app (SEO Basics for Your App)
Backups exist, and you know how to restore one
You'll know if it goes down (How to Know When Your App Is Down)

Part 5: get a fresh pair of eyes

You know how your app is supposed to work, which makes you bad at noticing where it's confusing. Ask two or three people to try it without instructions while you watch (in person or over a screen share). Don't help. Note where they hesitate, get confused, or get stuck. Those moments are as important as any bug.

Turning findings into fixes

Take your notes file to your AI tool, one bug at a time, with the details:

Bug: on /settings, clicking Save twice quickly creates two identical entries. Steps: log in, go to /settings, change the name, double-click Save. Expected: one save. Actual: two rows in the list. Please explain the cause, then fix it. Don't change anything else.

After each fix, re-test that specific bug and the journey around it — fixes sometimes break neighbouring things. Save your work with git after each one. (How to Write Good Prompts for AI Coding Tools.)

Make it repeatable

Save this checklist in your project. Run the happy paths and security checks again before every significant update. Once you're comfortable, ask your AI tool to turn the most important journeys into automated tests, so they're checked every time without you.

EasySpawn gives each branch its own live URL, so you can run through this checklist on a change before it replaces your live app. See how it works for AI-built apps or join the waitlist.