Helium adapters make it simple to physically connect the Atom Prototyping Module to popular embedded devices. The Helium Arduino/mbed Adapter is an easy-to-use shield equipped with two SMA connectors, an Atom socket and a few broken-out pins --- all in an Arduino R3 layout.
Also included with each shield is one 2.4GHz and one Sub-GHz antenna for optimal range and functionality. The best way to tell the difference between the two is that the shorter antenna will always be the 2.4GHz version.
Since Helium is a complete toolkit for building IoT applications that can connect to public clouds, a pre-built, secure connection from Atom modules interacts with what are called Helium Channels. Channels are a convenience layer between sensors and your organization’s cloud of choice that can connect to public clouds like Amazon Web Services, Azure, Google Cloud IoT Core or a private offering. Channels can also be used to send device data to applications and services via generic protocols like HTTP and MQTT.