For me at least, it’s a bit more complex to master than MySQL, but the freedom it gives you is incredible. MongoDB is great when your information is a bit more complex and you need very peculiar data structures, nested data, dynamic structures, etc.Also, I believe it’s a bit more difficult to distribute.

MySQL is great for simple tables where the data structures are not too complex, but it lacks some speed when you are trying to retrieve time data series.

Nonetheless, the free authentications are limited, so if you will potentially have millions of monthly authentications, it’s probably best to take the time to build it into your app directly.

Firebase is a great option for a very simple to implement, fast and reliable authentication method.

I’m not an expert, but I can tell you some things: MongoDB has a broader approval, being mentioned in 2189 company stacks & 2218 developers stacks compared to SQLite, which is listed in 314 company stacks and 477 developer stacks. Uber Technologies, Lyft, and Codecademy are some of the popular companies that use MongoDB, whereas SQLite is used by Intuit, Coderus, and Infoshare. Here's a link to MongoDB's open source repository on GitHub. MongoDB is an open source tool with 16.3K GitHub stars and 4.1K GitHub forks. 'Document-oriented storage', 'No sql' and 'Ease of use' are the key factors why developers consider MongoDB whereas 'Lightweight', 'Portable' and 'Simple' are the primary reasons why SQLite is favored. MongoDB and SQLite can be categorized as 'Databases' tools. A complete SQL database with multiple tables, indices, triggers, and views, is contained in a single disk file. SQLite reads and writes directly to ordinary disk files. Unlike most other SQL databases, SQLite does not have a separate server process. SQLite is an embedded SQL database engine. MongoDB was also designed for high availability and scalability, with built-in replication and auto-sharding SQLite: A software library that implements a self-contained, serverless, zero-configuration, transactional SQL database engine. MongoDB stores data in JSON-like documents that can vary in structure, offering a dynamic, flexible schema.

MongoDB vs SQLite: What are the differences?

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