Multiple phone numbers per SIM contact Some time ago I owned an Sony Ericson mobile phone. It was able to store a contact on the SIM card and add information like adress or multible phone numbers.

Why isn´t it possible to do the same thing on newer Smartphones?

I heard that old phones stored multiple contacts on the sim card by creating a contat for every information and combine it in the view, could that be true?
The SIM card isn't capable of managing complex records. Due to its limited storage, it only holds one phone number per contact, and also misses other details.

So when your "old phone" allowed for multiple phone numbers with one contact while storing the data on SIM, it must somehow have used multiple contacts, and displayed them in a kind of "merge view" (had it used some own format to achieve this, your SIM contacts would have become incompatible with other devices, so that approach is unlikely). While that would be doable on Android as well, it's not a standard for good reasons: How to tell which contacts to merge? By their name? There might be multiple "John Smith" entries, not necessarily pointing to the very same person.

As long as there's no standard defined, implementations might differ and thus leading to different results – which is the most likely reason it's not done at all.