What you definitely need: helmet, appropriate clothing, phone, passport (with visas), water and snacks.

必需品：头盔，适量的衣物，电话，护照和签证，水和点心。

youdao

From this he can monitor lighting, heating, temperature, phone and water usage.

从而他可以监测照明、采暖、室温、电话和自来水使用情况。

youdao

She had dropped her phone in the water and pretended to be dead, a tactic that required steely nerves because Breivik shot several apparent corpses just to make sure.

她的电话掉进了水里，假装自己已经死了，则需要非常强大的意志因为布莱维克向几具尸体开枪来确保他们真的死了。

youdao

In corridors where workers gathered, water and electricity, phone lines and computers were in full use.

CNN: No hope of finding more survivors at Pentagon

How do you expect people to take care of business like paying bills such as lights, gas, water, trash and phone?

FORBES: Minnesota Republicans to Ban Cash for Poor People, Limit Teacher Strikes

You should not submerge the mobile phone in water.

ENGADGET: Sony ships Xperia advance to the US, offers unlocked ruggedness for $300 or less