The big difference between a car and a boat is that, if it gets away from you, you might catch the car on your bike.
The HC-05 will not work with iPhone because it is a BT2 device. You need an HM-10, which is BT4. This is essentially a drop-in replacement for the HC-05, it is only about $1 more these days, and the Arduino code is the same. What's more, you get about three times the range, hence my original comment.