Application Cache
Beware of the deprecation of Application Cache.
With the help of cache manifest, mobile web app can work in offline.
1 Add it to home screen
2 Go to air plane mode
3 Or even restart the device
4 Open the game in offline mode and it works as normal.
Here is how it looks like in the HTML tag.
<html manifest="cache-manifest.manifest">
And here is the content of the manifest file, which contain all the assets file the Pie Guy game needs
CACHE MANIFEST # Version 1.0.3 index.html main.js images/about-text.gif images/default.png images/font1.gif images/game-over.gif images/guy1.gif images/guy2.gif images/guyFlip.gif images/chef0-1.gif images/chef0-2.gif images/chef0-flip.gif images/chef1-1.gif images/chef1-2.gif images/chef1-flip.gif images/life.gif images/map0.png images/map1.png images/menu-about-active.gif images/menu-about-small-active.png images/menu-about-small.png images/menu-about.gif images/menu-back.gif images/menu-back-active.gif images/menu-continue-active.gif images/menu-continue.gif images/menu-new-active.gif images/menu-new.gif images/menu-rotate.gif images/menuButton.gif images/notice-level.gif images/notice-time.gif images/notice-tokens.gif images/notice-total.gif images/pie-complete.gif images/bonus-score.gif images/scoreBar.gif images/splash.png images/token1.gif images/token2.gif images/token3.gif images/token4.gif