JSON 2 JSONP
Convert JSON to JSONP (on-the-fly) for easy cross-domain data requests using client-side JavaScript
Free JSON storage service. Ideal for small scale Web apps, Websites and Mobile apps.
JSONbin.io API is a free Development API that requires apiKey authentication, is served over HTTPS and supports CORS, so it can be called from the browser.
JSONBin.io is a free JSON Storage & a JSON Hosting service which is ideal for Web and Mobile apps, and also for JSON Mocking.
Details from jsonbin.io.

Unified API suite · now live
Geocode an address, validate an email, track a flight or pull stock data with one account, one dashboard and one API key.
Convert JSON to JSONP (on-the-fly) for easy cross-domain data requests using client-side JavaScript
Simple key-value storage REST API for quick prototyping
The JSONbin.io API is provided by JSONBin.io (jsonbin.io). JSONBin.io is a free JSON Storage & a JSON Hosting service which is ideal for Web and Mobile apps, and also for JSON Mocking.
Yes. The JSONbin.io API is listed in the Development category of the public-apis directory, which only includes APIs that are free or have a free tier. Check its documentation for rate limits and paid plans.
Yes. The JSONbin.io API uses apiKey authentication, so you need to register for credentials before making requests.
Yes. The JSONbin.io API supports CORS, so front-end JavaScript can call it directly.
Yes. The JSONbin.io API is served over HTTPS, so it's safe to use in production.