There are also cell signal boosters for inside

There are also cell signal boosters for inside your home or office.
If you are using a cell signal booster such as the Wilson Cellular Amplifier for your iPhone, you will rarely experience loss of signal, even if you are travelling in a car or train. This is because your cell signal is being amplified by an antenna that rests on your car. And since the antenna on your car is so powerful, you can have a car-full of cell phone users, and they will all experience increased cell service.
If you are always on the go, you will notice that your phone sometimes losses its signal, thus making calls or sending emails is impossible. Good thing that cell signal boosters are available, you will never have to worry about losing your phone's signal again. This cell signal booster works on the GSM, 3G and EDGE technologies, therefore it is definitely perfect for your iPhone.It's a major part of the car audio system and in turn, needs to be carefully thought about. Don't rush the process of buying an amp, as forgetting to check certain specifications may occur, which will then cause your amp not to work as well as it should.
When shopping for an amp, take a checklist. These may include, power, efficiency, signal to noise ratio, and price. The latter is important because it is vital that you get value for your money.
Most car audio enthusiasts will agree that power is probably the most important specification on the list. First of all, you need to purchase your speakers or subwoofers before your amp, and then match the spec with them. Knowing their impedance and efficiency will help you to decide what level of power you will need for them to work correctly. People tend to under power speakers or subwoofers, with amplifiers of a low power compatibility, which will of course cause a lower output.
It's always good to know the maximum output of an amplifier, in order to match it up correctly with your newly bought subwoofers or speakers. This will usually be found on the amp itself; however, these markings are not always accurate. Instead, go look at reviews of amplifier brands and if there markings are a true reflection of maximum power output.