Why is Service Worker not running on Chrome for Android?

Question

Currently I'm trying to build a web app using the Samsung Tab A. I thought this device would support Service Workers, cause following Can I Use says Chrome for Android 55 is required to run SW.

The tablet is running Android 6.0.1 (no more updates available) and Chrome 55.0.2, but unfortunately when the code shown below runs, the 'no sw' alert pops up.. The SW works fine in Chrome on desktop (mac OS).

if('serviceWorker' in navigator) {
  navigator.serviceWorker.register('/sw.js').then((registration) => {
    alert('sw');
    console.log('ServiceWorker successful, scope: ', registration.scope);
  }).catch((err) => {
    alert('no sw');
    console.log('ServiceWorker failed: ', err);
  });
}

Am I doing something wrong, or is it not possible to run SW on this kind of tablet? What else is needed if Chrome 55 isn't enough? I think there is some lack of information about this topic since I can't find the answer on this .. :(

Thanks in advance!

EDIT: I'd already enable multiple flags via chrome://flags without any success..

Answer 1

I was using ngrok to serve my webapp locally to my tablet. Did forget to use https..