Keyssa has proprietary technology that reportedly lets users transfer large files in a matter of seconds by holding two devices side by side.

Apparently Keyssa and Essential chatted about the technology and Keyssa “divulged to Essential proprietary technology enabling every facet of Keyssa's wireless connectivity”. Of course all of this was under an NDA.

Keyssa even deployed a team of 20 to educate Essential on its proprietary tech, sending them "many thousands" of confidential emails, hundreds of confidential technical documents, and dozens of confidential presentations.

After 10 months, Essential ended the relationship and told Keyssa that its engineers would use a competing chip in the Essential Phone.

Keyssa said Essential included techniques in its phone that were gleaned from their relationship, despite their confidentiality agreement.

One of the Essential Phone's key selling points was the option to swap in modular add-ons using the phone's unique cordless connector, which Keyssa claims is its tech.