Best way to control 12v circuits in a car.

Hey guys so I am working on a project for my show car.I got an android device fiberglassed into my front dash. Now I would like to have some sort of app/website I can design and when I click on, an led light will turn on or any 12v circuit.

I was originally gonna go with bluetooth and use an android app but then someone told me it would be better to use wifi, and have the car as a hotspot type deal.

so what would be the best arduino to go with and relay board I would need? if i use wifi id just have to design a website using html for the phone?

let us know ; whether you wanna control the 12v relay remotely or like wise. The car will be in 2meter of range you using bluetooth control it.

http://www.instructables.com/id/Android-controlled-Lights-and-Power-pfodDevice-fo/?ALLSTEPS

I want to control the relays with my android device that will be in the car. can be corded to the arduino

what is the best arduino to use?

You can go with Arduino Uno itself. Since you dont have lot of control perameter