Some devas are fellow Buddhists, in which case they can be respected as Dharma-protectors or even bodhisattvas. Apart from that, devas don't really feature in the religion aside from being characters in myths and moral examples, to show that even heavenly beings have the same basic problems we do.
As for communicating with them, I'd say they inhabit a more rarified conceptual realm, so whenever people feel a strong connection to a god or their iconography or feel as if they "speak to them" on a subtle level, that's basically what that is. It's not like you see a pillar of light and a multi-armed being descends and has a chat with you over coffee.