The Urban Airship Customize Preference Center iOS Sample Code demonstrates how to create and style a Preference Center providing a framework. Learn more at https://github.com/urbanairship/ios-tag-preference-center
A few years back Google introduced ML Kit, an SDK that lets mobile developers add machine learning to their apps. Recently, Google announced two new APIs (Entity Extraction and Selfie Segmentation) would be added to ML Kit to allow developers to create richer in-app experiences.
For a couple years I've thought about creating a geo-located tagging app. The idea is that anyone could use it like Delicious, but for tagging anything they want in the real world. Learning a mobile platform and creating the backend was always too much trouble for what is really just a fun little project. Now, I could write it in potentially less time than it's taking me to write this post. The Human.io API lets developers create mini-apps within its iOS and Android apps, with access to the camera and user location.