MongoDB Stitch is a cloud based backend as a service available only via MongoDB Atlas managed by MongoDB Team.
It offers API Layer over MongoDB, where extra layer of security can be configured easily, and also enable third party service integration easier then ever. Stitch lets developers to focus on building frontend application instead of managing data or integrating with services.

Stitch Use Cases:

What kind of application can be build using Stitch ?

  1. Stitch is useful to add new features in existing application or even if you are building new application, i.e., a) adding report dashboard to your existing application, b) allow support for profile image, 3) or add comment section to existing blog.
  2. Allowing third-party client's to access data from your existing application. i.e., allow users to get the stats of there activity on your website.
  3. Automate your events based task, i.e., you can monitor your stock on inventory and notify you via twillo text message when it reaches minimum configured threshold, or notify to all developers in a group on slack, whenever you make a commit on GitHub.
  4. Since Stitch also allows you to integrate directly with REST API, you can integrate with any service you can think of not enabled in Stitch services.

MongoDB provides built in components/framework to faciliate easy integration with third-party applications and for data processing, filtering, authentication :
1. Services
2. Pipelines
3. Rules

Services :

Are built-in third-party services that can be integrated in to existing applications without writting a single line of code, i.e., MongoDB provides below built-in services.
Amazon S3 - Amazon Web Services component, a key-value storage and static resource servicng.
Amazon SES - Amazon Web Services to send and receive email for events occuring from app.
Android Push Notifications - Push Notification from (GCM) Google Cloud Messaging.
Twilio Service - Messaging, voice, and chat services for web and mobile apps with Twilio.
HTTP Service - Integration with any third-party REST APIs.
[Slack Service]( Service) - A team-based messaging services.
Mailgun Service - Similar to Amazon SES, a way to send and receive email in response to events in your app.
GitHub Service - To Setup Webhooks from GitHub.
Read more on MongoDB Stitch Services

Rules :

MongoDB provides creation of rules on top of the services, to control the read/write access on fields.
Not to be confused with MongoDB Authorization, that is setup in the MongoDB itself, Stitch Rules instead determines if the specific fields are allowed by a Stitch service or not. Rules must be created for each collection that needs to be accessed. read more on MongoDB Stitch Service Rules

Pipelines :

If you are familiar with aggregation pipeline in MongoDB, then you are already know MongoDB Stitch pipelines, In Pipeline you define a sequence of actions to be performed, it consist of stages, and are executed in order, and output of each stage are passed as input to next stage and output of last stage is sent to applicaton. for each services there are respective actions provided by stitch. read more on MongoDB Stitch pipelines

Benifits :

Using MongoDB Stitch to build client application, slightly reduces the overhead of writting backend code and rules for the application, allowing developers to rapidly build and deliver application.