How to know if user prefers miles or kilometers?

Question

Hi,

In my app I've got a certain distance in meters.

And I want to display it in kilometers if user prefers kilometers and display it in miles if user prefers miles. And in the first case I want to add to a string "kilometers" at the end and in the second one to add "miles".

What is the best way to achieve this goal?

Thanks.

Answer 1

Why not make it a user preference?

Answer 2

Read this article about iPhone locale.

Answer 3

Unless the iPhone provides this information directly, you'll have to have a lookup table from locale to default unit. Then you should allow the user to override that default.

Answer 4

You could ask the user whether they prefer miles or kilometers, in a preference or something. Then whenever you display a distance you would say.

In pseudo c code

function distance(meters) {
    if (userPrefersKM) {
        return meters / 1000 + " kilometers";
    else if (userPrefersMiles) {
        return meters / METERS_IN_A_MILE + " miles";
}

Where METERS_IN_A_MILE would be about 1600, but you should look that up.