This is likely not possible as they run on different servers. But if you are tech savvy you can try to see if transferring save data works.
Here is a thread about transferring: http://ggnbb.glu.com/showthread.php?108690-The-Best-Way-to-Save-Transfe…
I'm not really sure it will, but I like the color as well :)
The dev team likes to give their NPCs a lot of exclusive stuff. In Stardom: Hollywood, we see the white hair too but it's never been actually released to us. :(
If you have gifted a Game Center friend that you have not either dated or co-starred with yet, they will automatically become love interests. It is not required that you date them. Marriage is not implemented in this game at this time.
If you have …
Buying cars means that you just use your car instead of the bus, but the cost is still the same. You do get more of the star/heart rewards from them than other furniture but that's only because the cost is higher to buy.
I recommend not using the "invite friends" button. Make sure you have directly added your friends to your Facebook account and not through the game. Make sure you and your friends have your permissions set in Facebook, by going to Facebook's Setting…
There is no cross-platform play. There is a whole bunch of information about adding friends at the KKH Forums.
There will probably never be cross-platform play because they run separately on different servers.