1. SYSTRAN.io - Translation and NLP API Documentation

SYSTRAN.io platform is a collection of APIs for Translation, Multilingual Dictionary lookups, Natural Language Processing (Entity recognition, Morphological analysis, Part of Speech tagging, Language Identification…) and Text Extraction (from documents, audio files or images).
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2. Open Weather Map API Documentation

Get weather and weather forecasts for multiple cities.
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3. Investors Exchange (IEX) Trading API Documentation

The IEX API is a is a free, web-based API supplying IEX quoting and trading data.
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4. REST Countries v1 API Documentation

REST Countries v1
Get information about countries via a RESTful API
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5. Breaking News API Documentation

MyAllies News delivers real-time news and stock pricing from across the globe and information on the latest breaking business and financial news.
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6. Botometer API Documentation

Botometer (formerly Truthy BotOrNot) checks the activity of a Twitter account and gives it a score based on how likely the account is to be a bot. Higher scores are more bot-like.
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7. Tripit API Documentation

TripIt organizes travel plans into an itinerary that has all of your trip details in one place. Simply forward confirmation emails to plans@tripit.com and TripIt will automatically build an itinerary for your trip that you can access anytime, either online or from a mobile device.
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8. FaceRect API Documentation

FaceRect is a powerful and free API for face detection. It finds faces (both frontal and profile) on the image specified by URL or uploaded as a file and is able to find multiple faces on a single photo, producing JSON output with a bounding box for each face found. Check out visual demo here: http://apicloud.me/apis/facerect/demo/. Note that additionally FaceRect can find face features for each detected face (eyes, nose and mouth). For more precise face feature detection please see our FaceMark API: https://www.mashape.com/apicloud/facemark
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9. Email Validator API Documentation

Checks for fake DNS as well as uses regex functions to check the email for the right length and accepted characters.
For example it will mark as valid an email like 'john@gmail.com' but it will recognize as a fake 'john@gmaill.com' (because of the not existing domain)
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10. OpenAPI 1.2 API Documentation

The TransLoc PublicAPI is a RESTful API which allows you to incorporate real-time vehicle tracking information into your web or mobile applications. It exposes several resources that allow you to access real-time information about transit systems tracked by TransLoc Inc.
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11. Crime Data API Documentation

Crime data is great for safe neighbourhoods.
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Please post more apis in comment i will add them in the post later :)
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