The Dropbox Datastore and Sync APIs have been deprecated, prompting developers to find alternative solutions. Chris Anderson suggests choosing open source projects to address this challenge. The focus shifts to migrating an existing app that uses the Datastore API, specifically the Lists-ios example app, to Couchbase Mobile and Sync Gateway. The changes involve setting up the database, saving documents locally, and initialising live queries. These modifications can be used as a starting point for other applications, including demo apps like ToDoLite-iOS and ToDoLite-Android, which use Facebook Login for authentication and access control rules defined in the sync function. Building a web client with Couchbase Mobile is also possible using Sync Gateway's REST API or PouchDB.