It would be great if @stephanritscher's patches could be merged into Fossify Contacts. I’ve been using his fork for a while and it works very well. Not only does it implement the correct address separation the vCard standard requires, it also provides country-specific formatting of the whole address on the contact info screen. (I can only attest the latter for German addresses where the postal code is shown correctly before the locality, whereas most apps just format every address according to US rules.) [Edit: I should have checked this first; apparently the app shows the postal code before the locality independent of the country of the address. I’ll have to investigate further if that is somehow specific to my phone's setup.]

Right now Fossify Contacts, same as the main-line Simple Contacts before it, stores the complete address in the street address field, which is just wrong; so I wouldn’t even consider this a feature request but a bug ticket.

Update: Since I’ve made the mistake of assuming the formatting feature mentioned above, I’ve made a corresponding feature request at stephanritscher/Simple-Contacts#18. Should proper address handling find its way into Fossify Contacts, the same would be nice to have here as well.

For context, here is the original Simple Contacts discussion of this issue:
SimpleMobileTools/Simple-Contacts#364

Apparently the developer @tibbi thought making the address format standards-compliant was too much of a “complication.”