Axure RP (Rapid Prototyping) is a development software and application used for creating interactive prototypes for websites, mobile applications, and other software products. It is a powerful tool for creating detailed wireframes, flowcharts, and sitemaps that help developers to create better designs and develop accurate functional specifications. Axure RP is used by web developers, product managers, and UX/UI designers to build and share functional wireframes, user flows, and interactive prototypes. It includes features such as drag-and-drop widgets, dynamic panels, advanced interactions, custom variables and events, and a built-in design library. It also allows developers to quickly create high-fidelity prototypes that are interactive and can be shared with stakeholders.
Balsamiq does not support interactive prototyping
I have used Pencil Project for a couple of projects and it is good for application design.