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CHAPTER 8

Wearable GPS

By Michael Hahn, March 2015

Wearables are great when you are on the go, especially when you are out for a run or looking for destination. It would

be great to just glance at your watch for your current location, rather than pulling out your handheld. Now that some

wearables have a built-in GPS sensor, you can continue to use location-based apps even when the wearable is not

paired with a handheld.

You implement location services in a wearable using the Google Play Fused Location Provider, just as you would

in a handheld. The Android operating system takes care of choosing the GPS sensor (wearable or handheld) and

implements any necessary communications between devices. The handheld GPS is preferred when both devices have

a GPS sensor, and the switchover between sensors is automatic when pairing status changes.

You can create your ﬁrst location-aware wearable app without writing a single line of handheld code. You don’t even

need to implement a handheld Activity. The section shows how.

8.1 First Wearable GPS

If you have not already done so, Create a Project . The new project wizard in Android Studio beta creates a project

with two main activities, one for the handheld device and another for the wearable. These two activities use the same

package name, which is essential for the wearable GPS to work.

8.1.1 Add Permissions and Metadata for Google Play Services

Modify the wearable manifest ﬁle to permit location service access and deﬁne Google Play Services metadata. This

example gives access permission for course location only.

<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />

...

</application>

Add Build Dependencies

Add the following build dependencies to the wearable build.gradle ﬁle (Module:wear) in the Gradle Scripts folder, if

necessary.

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