Vehicles kept in the UK must now be continuously insured unless a Statutory Off Road Notification (SORN) has been formally submitted. This requirement arose following a change in the law in June 2011 when a regulation known as Continuous Insurance Enforcement (CIE) came into force. The effect of this was that in the UK a vehicle that is not declared SORN, must have a valid insurance policy in force whether or not it is kept on public roads and whether or not it is driven.
Metromile also uses an OBDII-based system for their mileage-based insurance. They offer a true pay-per-mile insurance where behavior or driving style is not taken into account, and the user only pays a base rate along with a fixed rate per mile. The OBD-II device measures mileage and then transmits mileage data to servers. This is supposed to be an affordable car insurance policy for low-mileage drivers. Metromile is currently only offering personal car insurance policies and is available in California, Oregon, Washington, and Illinois.
Teenage drivers who have no driving record will have higher car insurance premiums. However, young drivers are often offered discounts if they undertake further driver training on recognized courses, such as the Pass Plus scheme in the UK. In the US many insurers offer a good-grade discount to students with a good academic record and resident-student discounts to those who live away from home. Generally insurance premiums tend to become lower at the age of 25. Some insurance companies offer "stand alone" car insurance policies specifically for teenagers with lower premiums. By placing restrictions on teenagers' driving (forbidding driving after dark, or giving rides to other teens, for example), these companies effectively reduce their risk.
But liability coverage levels come in threes — you’ll probably see something like 50/100/50 up to 250/500/250 in typical policies. You can think of these limits like: individual injuries / total injuries / property damage. Insurers are a little more technical, calling them bodily injury liability, total bodily injury liability and physical damage liability.