1. Waze- Free
Waze is more than just a navigation app. It not only tells you how to get where you're going it also tells you how traffic conditions are along the way. By driving with the app open, Waze can collect data about your drive, such as your speed and detours, and then use that info to give warning to other drivers. Waze users can also report speed traps and accidents which will inform nearby drivers using the app. Not only is Waze the best free navigation app, it is better than many pay apps, too.
2. INRIX Traffic- Free
INRIX Traffic tells you current state of traffic and predicts what the traffic will be in the next fifteen minutes or couple hours to give you an accurate departure time and arrival time. The app alerts you of incidents like accidents, crowds at major sporting events, and other traffic reported by its users. It also gives you a map of the local area with color coded lines indicating the amount of traffic in each area. The most exciting feature of this app is its ability to predict the traffic for the interval of time you plan to be traveling and then share that information with your friends and family!

3. GasBuddy- Free
It’s no wonder this app has nearly all 5 Star reviews in the app store, in a user friendly format GasBuddy posts gas prices in your area by different grades, including diesel, to help you find the cheapest place to fill up. By reporting gas prices in your area you can receive points and awards including being entered into a chance of winning $100 of free gas every day!
By easily selecting the type of car you have and the type of repair you need, this award winning app tells you how much you should expect to pay for a repair in your area. In addition its features allow you to track all your repairs as well as give you one touch roadside assistance.

5. Plugshare- Free
Covering over 40,000 stations worldwide, Plugshare helps EV and plug-in hybrid drivers find charging stations at malls, coffee shops, and parking lots. This app conveniently allows you to reserve a charger, pay for your fill up, identify fast or slow chargers, and countdown the charge time.
6. Car Minder Plus- $2.99
This app is a great tool for all your car maintenance needs. Although you'll have to input your car's maintenance schedule on your own using your cars owner's manual, for $2.99 this app will remind you about scheduled maintenance, keep track of your repairs, track fuel mileage, and on top of it all, manage multiple vehicles. Never again do you have to worry about when you last rotated your tires or changed your oil because with this app your info will be backed up on your computer every time you sync your iPhone! The best thing about this app is it’s easy to use interface that lets you record services and repairs in less than seconds.
7. Craftsman Garage Door App- Free
The Craftsman Garage Door App allows you to open your garage from any place you can get an iPhone signal. Why would you want to do that you may ask? Well if you are unsure if you closed your garage, this app can tell you. If someone making a delivery or a contractor working at your house needs to get in you can open it and close it when their done. Although the app itself is free, you’ll need to install the Craftsman Assure Link Internet Connected DC Chain Drive Garage Door Opener on your garage door available at Sears for about $230. IF this service is worth the cost to you, other features include a keyless entry pad and a 10-year warranty on its motor.

References
(http://www.edmunds.com/car-reviews/features/the-10-best-car-apps-for-smartphones.html)
http://electronics.howstuffworks.com/gadgets/automotive/5-iphone-car-apps.htm#page=3
http://www.popularmechanics.com/cars/how-to/products/7-ways-to-hack-your-commute?click=pp