I have traveled quite a bit to Italy and Spain over the past few years and all I have ever needed is the plug adapter. Electric razors, phone chargers, laptop chargers, and tablet chargers all work on 110-240 V and 50 to 60 Hertz. The wife's new curling iron works the same but her old one needed a voltage adapter. Every hotel we have been in has had blow driers. You can find voltage adapters on Amazon and all of them have multiple adapter plugs that will work on the different sockets you may encounter throughout Europe and Asia.
One other thing you might want to do is download Hotspot VPN if you want to watch Netflix, Amazon videos, etc. This VPS lets you spoof your IP location so you can get around the blocks that foreign countries put on these sites. It also offers an extra layer of protection when connecting to WiFi sites other than your own.