Comment by dfabulich

iOS Safari only allows push notifications for web apps added to the Home Screen, (as PWAs sometimes do), and that hasn't changed with the new Declarative Web Push. Most developers aren't familiar with this, and neither are users, and so it's very, very hard to educate users on how to allow you to push notifications.

Here's how it works.

First, users have to figure out how to add your web app to the home screen. There's no "Install" button that you can put in your web UI; users just have to know how. You can, of course, explain how, in your web page, but it's quite tricky. I'll explain it below; it takes like eight or nine steps.

First, the user has to click the Share button, the box with an arrow on it under the URL bar. On iPad, it's in the URL bar. It doesn't have the word "Share" on it, so if you use the word "Share" to describe it, users will get confused.

Also, the Share button may not be visible on the screen if the user has scrolled at all, because Safari collapses Safari's bar by default, but you can bring it back by scrolling back up to the top of the screen, or asking users to set up push notifications on a special page of your site that's too short to scroll.

Once they've clicked that, they need to find the "Add to Home Screen" button. On iPhone, "Add to Home Screen" is not visible by default either. The Share sheet is only half the height of the screen, and you have to scroll it to reveal more sharing options. One of the sharing options is "Add to Home Screen."

Once they've clicked that, they have the option to rename your app to whatever they want. You can control the default, but you can't prevent them from giving it a cute nickname, which they may forget later. Then, they can click the Add button.

When they click it, the sheet disappears. As far as the user can see, nothing useful has happened. But something has happened. There's a new app icon on their home screen. Not their first home screen, of course… it's probably their last home screen or something. There's no way for users to know which screen it's on. Or, they can search their iPhone for your app, if they can remember what it's called.

Anyway, once your web app has been added to the home screen, you have to tell your users to re-launch your app from that home-screen app launcher. It boots up slowly, slower than Safari, because it's running a whole separate process from Safari. (Also, JS in general just runs slower in home-screen web apps; only Safari is allowed to do JIT just-in-time compilation of JS.)

Finally, once they launch your app from your home screen, you can request permission to push. They have to click a button in your web UI (any click is fine), and then you can pop-up an iOS push permission request. If the user says no, you've missed your only chance; users have to go find your app in iOS Settings to turn on push.

Once users agree to push notifications in your home-screen web app, finally, finally, you can now send push notifications.