Indonesia

If you are afraid of losing your phone or stealing it, you can always opt to buy a phone on the spot with a prepaid sim card. You will find easily and for a ridiculous price.
If you prefer to use your own phone, if it is unlocked, you can get a prepaid card in the many mobile shops or convenient store.

Among the telephone providers in Indonesia, you can choose between telkomsel which the largest supplier in Indonesia. There is also Indosat or AXISworld ...

Regarding wifi, virtually all hotels and restaurants have their own connection. All you have to do is ask for access. Nevertheless, some areas where islands do not always have broadband. So be indulgent and patient or simply enjoy the place by disconnecting from the web.