I am looking for feedback about our solutions for rapid prototyping. We created an adapter for Arduino "Explore A" and several add-on modules, such as, sensors, drivers. This allows to quickly create a hardware for project.
Expansion board can be mounted directly on the adapter via castellated holes or pin headers.
Here is an example, GPS board mounted with pin header and gesture sensor with APDS-9960 mounted with castellated holes.
Product page (https://store.modulowo.com/en_GB/p/Modulowo-Explore-A-for-Arduino-Genuino/399)