I know there is a post that is kinda similar to this one, but this explains a bit more of the problem. I have tested this all out.
The problems are:
1. All my friends on my friend list have disappeared, note that blocked players are still showing.
2. I am not able to add players. It does not come up with the little pop-up saying that I have added this person nor does the person show on my friends list.
3. I can't search players, I have tried this with my own name so I'm pretty sure that I have gotten the name specific enough.
4. I lost all my furniture that I put in the little storage icon, I had a lot of furniture in there and was to bothered to remember what it all was.
5. I can't see players that are in guild A(example) it does not load, I gave it some time but it still dident load.

I am yet to descovers more annoying bugs that where recently implement.

P.S. I waited about a whole day, it did not go back to normal. I have also asked my guild members if they are experiencing sorta the same thing, they said yes.

~ PLEASE fix as soon as possible.  

Re purchase the app its fixed most of them problems for me  

This happened on iZone, however in my case I was only able to display one friend at a time. It was fixed a few minutes later, but still freaked us out.