You will need a QR code scanner such as Google Goggles in order to subscribe to friends' channel.
You will need to replace the default photo ID of your channel with an image of your choice before it is available to be subscribed by friends. You can still subscribe to friends' channel without activating your own channel.
All photos posted will last 3 days only.
You can post photos to friends' channel, just like posting to your own channel.
This app is implemented in MIT AI2, uses Google account management, Google Maps, Google Drive and Google FusionTables resources. The author is NOT affiliated to MIT or MIT AI2 team, nor to Google, Google Maps, Google Drive or Google FusionTables teams, in any way other than just a happy user.