Spent ages at Delhi airport yesterday trying to get it filled in as they would not issue me my boarding pass without it. Major issues were linking all of the flights and system not recognising airline and flight numbers. Also you have to scan your chip page, iPhone 12 struggled to do this, I can’t see how anyone with older phones will cope. Self picture recognition is a joke, trying multiple times to get the app to accept. Then the final page needs some sort of confirmation as the check in desk were not happy that it only came up as a review page.
I can see lots of unhappy travellers stuck at airports around the world with a sub standard overly complicated app being the cause.
It took an hour for me to fill in and raised my stress levels to an all time high trying to get out of a first time visited country.