This is a basic Foursquare client implemented as a packaged app.
It just displays recent checkins of the logged in user's friends. To log into Foursquare, it uses the identity API (specfically, the
launchWebAuthFlow method). Once it gets the OAuth token, it uses the storage API to persist it. It also uses the W3C Geolocation API to pass in the current location to the Foursquare API.
When running it unpacked, it will normally have a different ID (the unpacked
extension ID is a hash of the path on disk). However, this will result in the
auth API not working, since the redirect URL will be different. To force the
unpacked app to have the same ID, add this key and value to
(this is a base 64 encoded version of the app's public key)
The key must be removed before uploading it to the store.