Gifts for visiting other cities.

It seems to me the gifts are pegged to first time City visits. I haven't experienced gift bubbles on return visits to my most popular shopping destinations. 

It's completely based on how much money you spend in other cities. In other words, The more you buy, the more gifts you receive. It also seems to notice what you need and gives you all but 1 of that item. If you purchase a lot, you will see cash, similions and even keys. I get almost one key every 2 days. Enjoy

While I do buy a lot at the trade centers I have found that the visiting mayor bubbles appear to pop up at time intervals I live in GMT -7 (USA Mountain Time) and have noticed that bubbles are everywhere starting about 1am. I get a lot of bubble items from places I DO NOT purchase from. .I go trolling from bubbles every night starting at about 1am and there are bubbles everywhere. Now I am also noticing there are other similar times in the day but I have not been able to pin them down completely. They appear to be somewhere between 3 to 6 hour intervals. I will try to pay closer attention and report back. Again, when I am trolling for mayor bubbles I am not always buying. But I do agree with a first come, first serve basis on who gets them. I just try to be first.

OK, I have been running a check on when the mayor gift bubbles are reset and it appears to be at 4 hour intervals based on USA Pacific Standard Time (GMT -8), which is likely the EA office this game is run out of.

I have seen bubbles in most cities at midnight, 4am, 8am, noon, 4pm, and 8pm Pacific Time. A lot of bubbles are still there an hour later but are nearly gone 2 hours later. This had nothing to do with buying anything, which I didn't, or any other variable, just time. Remember, this is Pacific time (GMT -8). That is important. Hope this helps.

Nice work. I'll check it out. I'm on the East Coast so these are reasonable times as well. Thanks!