The man difference between a line amplifier and a mobile signal repeater is the type of signal they amplify .a line amplifier amplifies a wired signal ,such as an ethernet or coaxial cable signal . a mobile signal repeater amplifies a wireless signal . such as a cellular signal . 

Here is the summarizing the key differenes between line amplifiers and mobile signal repeaters : 

Type of signal amplified - line ampilfier :wired 

                                         mobile signal repeater : wireless 

Components - line amplifier : amplifier ,coaxial cable ,connectors  

                         mobile signal repeater : amplifier ,external antenna ,internal antenna 

Installation - line amplifier : easy to install 

                     mobile signal repeater : more complex installation 

Coverage area - line amplifier : limited  

                           mobile signal repeater :can cover a large area 

Cost -  line amplifier :Less expensive 

            mobile signal repeater :more expensive 

Line amplifiers are typically used to improve the signal quality of wired devices ,such as computers and routers. they are also used to extend the reach of a wired signal over long distances . mobile signal repeaters are used to improve the signal quality of celluar devices .such as smartphones and tablets .they are also used to extend the reach of a celluar signal to areas that are not well-served by cell towers . 

If you are having problems with a wired signal , such as slow internet speeds or dropped connections , then a line amplifier may be a good solution for you . if you are having problems with a wireless signal ,such as dropped calls or poor data speeds ,then a mobile signal repeater maybe a good solution for you . 

Here are some additional things to consider when choosing between a line amplifier and a mobile signal repeater :

The type of the signal you need to amplify . 

The size of the coverage area you need to improve . 

The cost of the device. 

The ease of installation . 

If you are not sure which type of device is right for you , it is best to consult with a professional .