Web App Manifest sample file.

manifest.json

{
  "name": "JavaScript Store",
  "short_name": "JavaScript Store",
  "lang": "en-US",
  "start_url": "/",
  "display": "fullscreen",
  "orientation": "portrait",
  "theme_color": "#f2e058",
  "icons": [
    {
      "src": "/icons/icon36.png",
      "sizes": "36x36",
      "type": "image/png"
    },
    {
      "src": "/icons/icon48.png",
      "sizes": "48x48",
      "type": "image/png"
    },
    {
      "src": "/icons/icon60.png",
      "sizes": "60x60",
      "type": "image/png"
    },
    {
      "src": "/icons/icon72.png",
      "sizes": "72x72",
      "type": "image/png"
    },
    {
      "src": "/icons/icon76.png",
      "sizes": "76x76",
      "type": "image/png"
    },
    {
      "src": "/icons/icon96.png",
      "sizes": "96x96",
      "type": "image/png"
    },
    {
      "src": "/icons/icon120.png",
      "sizes": "120x120",
      "type": "image/png"
    },
    {
      "src": "/icons/icon152.png",
      "sizes": "152x152",
      "type": "image/png"
    },
    {
      "src": "/icons/icon180.png",
      "sizes": "180x180",
      "type": "image/png"
    },
    {
      "src": "jsstore.png",
      "sizes": "192*192",
      "type": "image/png"
    }
  ]
}