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   OX COI Messenger

Email has never been so instant.

Discover how you can chat via email with OX COI Messenger. Test the beta version now on your smartphone!


Developer? Check out the sourcecode here.

No sign-up needed.

You can use any email account and start chatting right away. Keep in touch with all your friends, family and colleagues. If they do not have the COI Messenger app yet, they will still get your messages – as emails.

Send media files and stay secure.

Send and receive texts, voice messages, photos or documents. Your messages are encrypted automatically.

Stay in control.

OX COI Messenger works with any email provider. You choose whom to trust and where your data is processed and stored. Your credentials never leave your phone.

OX COI Messenger Beta

This short video shows how email can look by using the new OX COI Messenger. The video takes you through all the main features and introduces you to the new face of email.

Introducing COI

This bootleg video was taken at the Open-Xchange Summit in Madrid where CEO Rafael Laguna and PM Robert Virkus explain how COI was taken from conception to Beta.