Before you visit Vietnam you want to bring 2 things in your bag.
1- A network cable: most hotels here have a network hole in the wall and a cable will cost you around 3$ a day. So bring a cable.
2- A mini wireless router: its size is less than half the size of regular router and it'll cost you around 45$, but not in Ho Chi Min. you wouldn't find one here, and a regular will cost you 185-250$.
other than that, the cafes and restaurant here are all WIFI.
Paradiso!

 

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