Today mobile apps are everywhere. These apps cannot count on a reliable and constant internet connection: working in offline mode is becoming a common pattern. This is quite easy for read-only apps but it becomes rapidly tricky for apps that create data in offline mode. This talk is a case study about a possible architecture for enabling data synchronization in these situations. Among the topics covered:

* overview of the existing solutions
* id generation
* hierarchical data
* managing different data types
* sync algorithm