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Apps

In Ditto, an app is a grouping of collections. All applications that embed the Ditto SDK and share the same app ID will automatically form a mesh network and synchronize data with each other, either directly or via Ditto Server. While the name “App” suggests that a single Ditto app is a single application, it is common to have multiple Ditto-enabled mobile applications use a single Ditto app. For example, in the context of a point-of-sale system, a single Ditto app is likely to be used by both the kiosks and the displays in the kitchen, even though these are two distinct mobile applications.

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Collections

Ditto stores documents in collections. Collections are analogous to tables in relational databases. Collections allow you to group similar documents together within the same namespace.

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Structuring Collections

While it is good practice for documents within a collection to share a similar structure — for instance, all car-related documents stored in the cars collection contain fields 'make', 'model', and 'year' — structural uniformity is not mandatory. There is no limit to the number of collections you can have in your data model, so create as many collections as you need.

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Managing Collections

Every document must be associated with a collection, even if only one document exists within that collection. There are no explicit steps to manage collections; Ditto implicitly creates collections when you first store data for that collection.

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Querying Collections

When querying, database interactions occur with collections rather than individual documents. For instance, the query below searches the entire cars collection once executed. 
SELECT * FROM cars
You can read more about accessing data within collections in Accessing Data.