From Engadget · Novak Božović · · 2m
Tech upgrades worth making to your car
Skip the full stereo replacement. A Bluetooth adapter or portable CarPlay display can modernize an older dashboard without tearing it apart.
In brief
Skip the full stereo replacement. A Bluetooth adapter or portable CarPlay display can modernize an older dashboard without tearing it apart. Match your upgrade to what's actually missing: wireless audio needs only a simple adapter, while navigation and phone controls require a portable display or head unit…
Skip the full stereo swap
Older cars don't need complete sound system replacements just to get Bluetooth and CarPlay. A simple adapter or portable display can add wireless audio and navigation without touching the factory radio.
Start with Bluetooth receivers

If your car has a 3.5mm AUX input, a Bluetooth receiver is the easiest upgrade. Your phone connects wirelessly to the receiver, which sends sound through the existing AUX jack without any dashboard work.
FM transmitters for cars without AUX
No AUX port? A Bluetooth FM transmitter plugs into your 12-volt socket and broadcasts audio on an unused FM frequency. The downside is interference from nearby radio stations, especially on long drives.
Add a portable CarPlay display

Want maps and phone controls on screen? A portable CarPlay or Android Auto display mounts on your dashboard like a GPS unit. It connects to your phone and plays audio through your existing speakers.
Wireless adapters have limits
Wireless CarPlay and Android Auto adapters only work with cars that already support the wired versions. They can't add these platforms to older stereos that never had them built in.
Replace the head unit for permanence

An aftermarket head unit replaces your factory stereo with a touchscreen system that includes Bluetooth, CarPlay and Android Auto. Check compatibility first, as some cars need special wiring harnesses to keep steering wheel controls and backup cameras working.
Fix sound quality separately

If your car already has the connectivity you want but sounds weak or distorted, upgrade speakers, add an amplifier or install a subwoofer instead of replacing the whole system.
In short
Match your upgrade to what's actually missing: wireless audio needs only a simple adapter, while navigation and phone controls require a portable display or head unit replacement.

