Use this iOS SDK to interface with the AerisWeather API. AerisWeather is a weather app providing access to data sets like tides, moon and sun cycles, fires, earthquakes, forecasts, and records. The SDK is developed and supported by AerisWeather. See the project page for detailed SDK and API documentation as well as samples and a demo project.
Onset, a supplier of data logging devices, just launched the HOBOlink® Web Services API, that enables anyone to easily build applications around weather, energy and environmental data gathered from the Onset HOBO® U30 monitoring systems, hardware you install in your environment which can share its status up to Onset's system.
Forecast, the team that created the acclaimed iOS weather app Dark Sky, has created an API that brings its gorgeous weather data and display into any platform. As Forecast put it, they wanted to transcend their work with Dark Sky.