laptop
Definition:
A laptop is a portable computer that is small enough to sit on a person's lap. Laptops are battery powered so you can use them wherever you go.
Here's a word you may not know...
roaming
Roaming occurs on mobile phones when the mobile phone is communicating with another cellular network outside of its geographic area. If the two cellular networks have an agreement with one another, the mobile phone is allowed to utilize the neighboring network. Some cellular providers charge a premium when placing calls while roaming on another cellular network. Your mobile phone should indicate when it is roaming.