I have study how develope apps for android by using react-native. I was make simple app like "Hellow World", and build it in expo.

From command line I was run:

exp build:android
We've built a brand new CLI for Expo!
Expo CLI is a drop in replacement for exp.
Install: npm install -g expo-cli
Use: expo --help
Read more: https://blog.expo.io/expo-cli-2-0-released-a7a9c250e99c
[19:07:57] Checking if current build exists...

[19:07:59] No currently active or previous builds for this project.
[19:08:01] Publishing to channel 'default'...
[19:08:03] Building iOS bundle
[19:08:04] Building Android bundle
[19:08:04] Analyzing assets
[19:08:06] Uploading assets
[19:08:06] No assets to upload, skipped.
[19:08:06] Processing asset bundle patterns:
[19:08:06] - /home/xxx/projects/wtf/assets/*
[19:08:06] Uploading JavaScript bundles
[19:08:09] Published
[19:08:09] Your URL is

https://exp.host/xxx/wtf

[19:08:09] Building...
[19:08:10] Build started, it may take a few minutes to complete.
[19:08:10] You can check the queue length at
 https://expo.io/turtle-status

[19:08:10] You can monitor the build at

 https://expo.io/builds/4eb3dae0-d227-4732-a6db-1a1953a79b0d

|[19:08:10] Waiting for build to complete. You can press Ctrl+C to exit.
[19:25:21] Successfully built standalone app:

And application was build well. I was download apk from Expo site, and try to install on android. When it was installing, I get error with message like this:

Play Security could not find developer information. Applications from unknown developers may not be safe.

Attention question. How can I make my application secure? I could not find information about this. So that it is installed without disabling android protection.

My app.json looks like:

{
  "expo": {
    "name": "wtf",
    "slug": "wtf",
    "privacy": "public",
    "sdkVersion": "34.0.0",
    "platforms": [
      "ios",
      "android",
      "web"
    ],
    "version": "1.0.0",
    "orientation": "portrait",
    "icon": "./assets/icon.png",
    "splash": {
      "image": "./assets/splash.png",
      "resizeMode": "contain",
      "backgroundColor": "#ffffff"
    },
    "updates": {
      "fallbackToCacheTimeout": 0
    },
    "assetBundlePatterns": [
      "assets/*"
    ],
    "ios": {
      "supportsTablet": true
    },
    "android": {
      "package": "com.wtf.wtf"
    }
  }
}

Waiting for the application to install on android.