Bolt is a point to point zero delay transmitter that utilizes RF over the 5GHz spectrum. It cannot stream to iPads, over IP networks, or to the Internet.
Cube utilizes H.264 compression and transmits video over IP networks. Cube can stream to iOS devices, over the Internet, and directly to the Web using WiFi, Ethernet, or 3G/4G networks. Cube encoders are not zero delay; 7-8 frames latency to iOS devices, and as low as 4-5 frames to a decoder.
Together the Cube and the Bolt make a great team providing zero delay to a monitor and minimal delay to iOS devices and offering the ability to capture proxies.