Looks like it’s the app issue then.

You got no choice but to update to ios26 or else most of the apps won't work in the future

Well, if so apple will definitely release fix update for it 🙂

Yes, apps issues, can't take risk by changing Fon again, cos the apps are my livelihood

Will wait for others users to use & if got any bugs or compability issues before I downloaded it

Wait a feedback and if it's okey then you will update to ios26, but i don't think there is a perfect system software, even android also the same, that's why they will release fix update few days later if there is glitch or bugs reported

Can iOS return & downgrade to previous version if newly download version is buggy ?

Backup first thru itunes, then update to ios26, anything can revert back to previos ios

Looks not easy, my laptop is more than 10 years old.

Then stick to the current ios18.5.2 until most of your apps no longer support

Yes agreed with you, cannot take risk too risky if later apps incompatible

superior & better is subjective. Some people think Microsoft Office is better, some prefer the like of open source such as Libra Office etc. Some love Windows, some might like Linux.

If you change new phone, you need to cancel the Mydigital ID cert and re-register. Can do it through Mydigital ID kiosk or request cancellation of your cert through the app on your new phone.
Without cancelling your cert you cannot re-register on the new phone.
Not really. Many apps, such as WhatsApp are supported way back until iOS 16 even.

yes but will be a lot of work. You need to download the previous iOS and restore it. Only can be done within 1 week after iOS released, after which apple will stop signing older iOS and close the window for downgrade.

Thanks man. No wonder I can't get mydigital Id to login on my new Fon. Very trouble some this app.

For the rest, it's too complicated for me to understand

Noted