[rpbertp13]

Cellular data networks in many parts of the world deliver incredibly slow speeds. In those places, the hassle of finding and connecting to a WiFi hotspot is often worth it. I'm currently traveling in the Philippines and malls, restaurants and cafes commonly offer WiFi to attract customers, and it works.

Even when the local network is fast, buying a SIM card may not be an option if your phone is locked and under contract, which is very common for US users.

[ekianjo]

Buy a (used) Sim-free phone that's 2-3 years old, it's dirty cheap and will save you much trouble.