Okay found out what's going on. Apple, as usual (like with charger leads) they've gone their own way. So they're not supporting Progressive Web Apps because they'd ruin their App Store revenue.
So Apple devices suck, I mean don't have the ability to install a PWA (Progressive Web App) as yet.
So I think those struggling to find the notification to install it (which even pops up on Windows computers, let alone Android Tablets and Phones, are all using them overpriced underpowered outdated Apple devices still knocking about a bit lol
Give me a feature on an Apple device that you keep overpaying for but insist is better, and I'll find you an Android device with twice the 'power' or 'camera pixels' or RAM etc at half the price.
When app developers made apps for iPhones first, years ago, they were worth buying. But these days app developers make Android apps first, if make an Apple version at all. There are 3 times the Android phones on the market than iOS ones.
You're behind the times people.
Switch over on your next phone upgrade, or even better, just buy the phone outright annually and have a £20 a month tariff that gives you unlimited calls, texts and data. Can even get dual sim phones and have a work sim and personal sim and install two Whatsapp's, two Facebooks, two everything - one for each sim.
It's the future.