I'm going to do some traveling in the next few weeks and purchased the World Travel Adapter Kit from Apple for my iPad and iPod Touch. I also intend to take my Galaxy Tab 7 plus and I'm trying to keep down my cable/adapter mess. The adapter kit is listed as 5.1v and 2.1 amps. The adapter for the Samsung has no voltage listing (that I've been able to locate thus far) but it is 2 amp. Can I use the same adapter for all 3 units? Note: I just found that it is 5 volts for the Samsung ac adapter. One more thing: Can I plug in an unpowered usb hub so I can charge multiple items at the same time?