# Testing your app

> Try everything before launch. Testers, test keys and pretend $LIA, running your page from your computer, the SDK demo, and finding problems inside Lia. From the Lia developer docs: https://docs.lialabs.org/guides/testing

## Test mode

New apps start in test. While they are:

- Only you and your testers can open the app. Ask the Lia team to add testers by their Lia usernames.
- Lia's header says **Test** next to your developer name.
- Payments and rewards use pretend $LIA; nobody's balance moves.
- Use your **test key** on your server. It only sees test sessions, charges and players.

See [Test and live](/concepts/test-and-live) for everything that's different.

## Run it from your computer

Lia only opens https pages from your app's address, so a page on `localhost` can't open in Lia directly. Put it behind an https tunnel, and ask the Lia team to point your test app at the tunnel's address:

```sh
npx vite --port 5173
cloudflared tunnel --url http://localhost:5173
```

A named tunnel (or any fixed https address) saves asking for a new address each time.

## In a normal browser

Outside Lia, `Lia.available` is `false` and every call fails with `not_in_lia`. For working on layout in a desktop browser, a small stand in helps:

```js title="dev-lia.js"
// Only when not inside Lia, and only in development.
if (!window.Lia.available && location.hostname === "localhost") {
  const fake = { player: { id: "p_dev000000000000000000", name: "you" }, session: "dev", exp: Date.now() + 9e5, mode: "test", language: "en", rtl: false, platform: "web" };
  window.Lia = Object.assign(Object.create(window.Lia), {
    init: async () => fake,
    ready() {},
    session: async () => ({ session: "dev", exp: Date.now() + 9e5 }),
    toast: async (text) => console.log("toast:", text),
    haptic: async () => null,
    pay: async (productId) => ({ chargeId: "ch_dev", productId }),
  });
}
```

Your server won't verify `"dev"` sessions, so keep a development path there too, or test server flows inside Lia.

## The SDK demo

Lia's own demo app tries every SDK call and shows what comes back: `https://api.lialabs.org/sdk/demo`. It opens inside Lia for people the team adds as its testers; ask if you'd like to try it. Its source is a good reference for each call.

## Finding problems inside Lia

Lia's store builds don't allow attaching a web inspector to your page. Instead:

- **Show errors on screen** while testing: a small log panel your testers can screenshot.
- **Send errors to your server** with the player id, `Lia.version`, `Lia.platform` and the error's `code`.
- **Check every rejection's `code`**, not just its message.

```js
window.addEventListener("error", function (event) { report({ message: event.message, at: event.filename + ":" + event.lineno }); });
window.addEventListener("unhandledrejection", function (event) { report({ code: event.reason && event.reason.code, message: String(event.reason) }); });
```

## Before you go live

- Payments: buy each product, close the sheet without paying, reload mid payment and check `Lia.charges()` finds it, and refund one.
- Webhooks: a test purchase reaches your handler, its signature checks out, and a second delivery does nothing.
- Rewards: a duplicate key pays nothing; `pool_empty` and `daily_limit` are handled.
- Notifications: ask, send, tap one with your app closed and with it open.
- Looks: light and dark, a right to left language (Arabic), a small phone, and fullscreen if you use it.
- Your server switches to the **live key** in production, and nothing from your test data leaks into live.

Then ask the Lia team to switch your app to live.