Smartphone-vehicle integration: Making sense of the cacophony

Advantages
The cloud service model opens up new possibilities for in-vehicle infotainment systems:

New services — new features and services can be easily added to a vehicle's infotainment offerings.

User control — users can subscribe and unsubscribe to services offered through the cloud

Updates — updates and upgrades to applications are the responsibility of the service provider, though upgrades to the small in-vehicle HMI applications may occasionally be needed

Independence —connectivity can be directly from the vehicle, or through a smartphone.

Disadvantages
The cloud service model has some important limitations:

Connectivity — the cloud service model relies on a continuous, high-throughput connection to the cloud. It is of little use in areas with poor or no mobile coverage, for example, outside urban areas and transportation corridors, or in urban canyons.

Limited usefulness — the relatively high possibility of a cloud service becoming even temporarily unavailable restricts its usefulness to non-essential applications, or applications with "soft-failure" designs.

iPod Out

With this model, the iPhone or iPod runs the show. It has the media libraries and applications, and it runs all applications and controls the user interface. USB or Bluetooth provide connectivity between the portable device and the vehicle. If an iPhone is used, it can be used to make and receive calls.

After an initial handshake, the head unit does nothing more than serve as a conduit for audio and video from the device to the vehicle speakers and screens, and for commands from the in-vehicle infotainment controls (up, down, next, select, etc.), which are delivered to the device using the iPod accessory protocol.

Advantages
The advantages of the iPod Out model include:

Simplicity — the iPhone or iPod looks after everything. The automaker's responsibilities go no further than setting up the head unit to be able do a handshake with the Apple devices, pass them commands from the in-vehicle controls, and pass the device audio and video out to the vehicle speakers and screens.

Familiarity — the HMI is familiar to users, who, presumably, use their iPhones or iPods when they are not in the vehicle.

Future-proof — Apple can update iPods, iPhones and applications without automakers needing to change or revalidate anything to stay current

Car-centric interface — Apple developed the iPod Out interfaces in consultation with BMW to ensure that it is appropriate for in-vehicle systems. Limited options reduce possibilities for driver distraction.

While it is not, strictly, a design advantage, the popularity of iPods suggests that a vehicle infotainments system that did not implement iPod Out support will needlessly put itself at a disadvantage.

Disadvantages
Despite, or perhaps because of its simplicity, the iPod Out model has some drawbacks:

Dependency — with the head unit reduced to a conduit for commands and output, the entire system becomes dependent on what is offered by the external device — and on the future of this device.

Proprietary — iPod Out is only implemented by Apple. Unless they want to restrict their customers to only those who have Apple devices, automakers should implement this model as a complement to other models.

Limited functionality — the iPod Out model only supports audio playback and mobile telephony. In order to ensure that the application HMIs designed for portable devices do not cause undue driver distraction, other applications are not accessible through the head unit.

UI design — users may find using both the iPod interface and the vehicle-specific interface irritating and even distracting.

Branding — with the iPhone or iPod providing and controlling the display, automakers lose the ability to maintain their vehicle brand in the infotainment system HMI. For example, a driver will not be driving, say, a Lexus with a great Lexus infotainment system, but a Lexus with an iPhone infotainment system.