chrome-extensions-samples/appsquare

- Basic Foursquare client implemented as a packaged app.
- Just displays recent checkins.
- Uses the storage API to persist the auth token locally
- Uses the identity API to do the OAuth dance in a separate window
- Uses the geolocation API to pass in the current location to the API

The app is listed in the (internal) Chrome Web Store at:
https://chrome.google.com/webstore/a/google.com/detail/hgdbciackkmabepeodkkdipmbjnfojmm

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 manifest.json:

"key": "MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQDnyZBBnfu+qNi1x5C0YKIob4ACrA84HdMArTGobttMHIxM2Z6aLshFmoKZa/pbyQS6D5yNywr4KM/llWiY2aV2puIflUxRT8SjjPehswCvm6eWQM+r3mB755m48x+diDl8URJsX4AJ3pQHnKWEvitZcuBh0GTfsLzKU/BfHEaH7QIDAQAB"
(this is a base 64 encoded version of the store app's public key)

The key must be removed before uploading it to the store.