I've seen some users struggling / searching for free APIs, so I'm going to list out some free(mium) APIs I found. This topic is made wiki so eveybody can expand the list.
[@NishyanthKumar] 7Timer! - numerical weather forecast for anywhere over the world
https://covidtracking.com/data/api (this only allows you to see data before March 7, 2021)
https://covid19api.com (I haven't used this one yet)
Coronavirus COVID19 API (from postman.com)
LanguageTool API Documentation (dnaber) | RapidAPI (from RapidAPI)
Spelling Corrector Extension 📝 (@Yash_Sehgal22’s self made API extension)
IP Tracker Extension Free Update v2 - Extensions - Kodular Community (An IP Address extension)
http://ip-api.com/json (this link works just when you click on it, and it returns in JSON format)
Decathlon Developers (@Gordon_Lu)
[@HEART12] Weather API - OpenWeatherMap
[@Gordon_Lu] API - MetaWeather
7Timer! - numerical weather forecast for anywhere over the world (doc language set to English)
Weather Mate ☁ [free] (@Yash_Sehgal22's self made weather API extension)
AerisWeather API Documentation (aerisweather-aerisweather) | RapidAPI (from RapidAPI)
[@cafedev] Home page | Open-Meteo.com
[@HEART12] [HOWTO] Get Google's Search Results Without Extension!
GitHub - public-api-lists/public-api-lists: A collective list of free APIs for use in software and web development 🚀 (Clone of https://github.com/public-apis/public-apis) (GitHub source, thanks to @Peter )
(TIK TOK API, @HAM_APK ) TikTok for Developers
[@AyProductions] Free API - Huge List of Public APIs For Testing [No Key] - Apipheny
How do I deal with URL get requests?
Check out the company's documentation first. See if it requires an API key or it needs special parameters.
What is a parameter?
A parameter is some data you add to a Web URL get request. Some parameters are optional, but some are required. The first parameter is joined by '?' and the rest is joined by '&'. Of course, some API get requests do not need APIs, so...
For example, in weatherapi.com, if you want to get the current weather JSON data from Hong Kong, you have to get an API key first. If your API key is AICODE, then your URL is (referenced from the documentation):
After your URL is set, you need to analyze this JSON (think about it - is it a list of dictionaries, dictionary of dictionaries, or others?). You can use a Web component to both turn JSON to lists / dictionaries and getting a get request.
Links that might help you
How to implement any API in my app - Discuss - Kodular Community (Kodular community link)
How To Read a JSON API Data in Kodular - getting Values from JSON - Appybuilder - Kodular - YouTube (YouTube video)