JayDB vs PouchDB

JayDB is a JSON document database with per-user sign-in, aimed at static apps that need user, session, or tenant data without an app-owned backend. Documents are JSON at slash-separated paths, and the first write creates the namespace. Its REST data plane supports GET, PUT, DELETE, and prefix listing. Browser apps can authenticate through OIDC with Authorization Code and PKCE without embedding a client secret. Listed identity providers include Google, GitHub, Microsoft, generic OIDC, and custom OAuth2. The official SDK supports authentication, token refresh, typed document access, and compare-and-swap operations. ETag-based compare-and-swap may reject a write with HTTP 412 if the document changed since it was read. JayDB is available as managed cloud software or as a self-hosted Go engine under the MIT license, using S3-compatible storage or local disk. The free plan is free and includes 1 GB stored, 100,000 reads per month, and 10,000 writes per month; usage hard-stops at those allowances. Metered rates are $0.05 per GB-month of storage, $0.20 per million reads, and $0.50 per million writes.

PouchDB is a free, open-source JavaScript database for storing application data locally and synchronizing it with CouchDB and compatible servers. It keeps data available offline and can sync local and remote databases after a connection returns. Its replication API can follow later changes and retry after connection failures when configured. PouchDB runs in browsers and Node.js, as well as Cordova, PhoneGap, NW.js, Electron, and Chrome apps. Browser storage defaults to IndexedDB, while Node.js defaults to LevelDB. Documents can include image or audio attachments stored as base64 data or Blobs. PouchDB includes a map/reduce API; Mango queries require the separate pouchdb-find plugin. Its asynchronous API supports callbacks, promises, and async functions, and the project names Angular, React, Ember, and Backbone as framework examples. Listed compatible servers include CouchDB 1.x, 2.x, and 3.x, Cloudant, and PouchDB Server. Replication requires a backend that speaks the CouchDB replication protocol. The project homepage says Apache PouchDB is undergoing incubation at the Apache Software Foundation.