Smartphone Navigation Systems
You already have one: Factory-navigation skeptics argue that smartphones are an alternative to an expensive factory system, noting that phones already have a map application, and that's all you really need. Given the quality of the maps from Apple and Google, we're inclined to agree that they are good enough for most people. That said, there are a few limitations to keep in mind. More about those later.
Traffic data: In many cities, the fastest way to get from A to B isn't necessarily the shortest path; it's the one with the least traffic. Smartphone apps have excellent traffic data and access to Waze, the community-based traffic app. Factory nav systems may have live traffic data, but you have to pay for a subscription once the trial has ended.
Current maps and points of interest: Smartphone maps will never be out of date, and any updates are always included. The same goes for the names and addresses of any points of interest you want to visit.
Convenience: Smartphones let you input an address as you walk to the car, leverage your contacts for their addresses, have a calendar app to remind you that you need to leave at a certain time, and then route you there. All those things happen in a faster interface with typing that's easier than the input method required by other systems.
Integrated smartphone options: Apple CarPlay and Android Auto offer the convenience of smartphone navigation with the integration and safety of a built-in system. They offer the convenience of smartphone navigation but with a larger screen display. That reduces the potential for distraction.
Distraction: Unless you have Apple CarPlay or purchase a car mount for the phone, it will most likely sit in a cupholder. And since you'll have to take your eyes off the road to check the directions, this can be just as much of a distraction as texting while driving. The mount itself can cost from $20 for a basic unit to $100 for a do-it-all mount that will charge the phone and boost the audio and GPS signal.
Spottier reception: Most of the native map applications rely on a cell signal for their map data. If you lose cellular coverage, you may find yourself unable to use the maps and directions. Apple and Google offer the ability to download certain maps for offline use, but it takes more preparation and hard-drive space on your phone (up to 1.7 GB on Google Maps). And without a cellular signal, you won't have access to traffic info, alternate routes or lane guidance.
Battery drain: Running a navigation application on a smartphone can sometimes take a toll on its battery, which makes carrying a phone car charger more important. It can also be an added cost if you don't already have a charger.