What can developers create with the help of ArcGIS Online APIs?

Developers can create custom applications utilizing ArcGIS functions by leveraging the ArcGIS Online APIs. These APIs provide access to a wide range of ArcGIS capabilities, including mapping, spatial analysis, and data management. By utilizing these APIs, developers can build tailored solutions that meet specific user needs, integrate location-based data into their applications, and enhance functionality with GIS features. Custom applications can be web-based or mobile, allowing for diverse deployment options and improving users’ interaction with geospatial information.

While other options, like creating new hardware solutions or standalone platforms, may not be achievable through the capabilities provided by ArcGIS Online APIs, the focus on developing custom software applications directly aligns with the intent and design of these APIs, making this the correct choice.