The differences between Cyanogen OS and CyanogenMod are sometimes a bit difficult to see. The main difference is that CyanogenMod is the community-based ROM we all know and love. And Cyanogen OS is the OS that is shipped on Cyanogen phones like the OnePlus One, Micromax YU Yureka and many others.
Cyanogen has been rebuilding the Messaging app that is part of Cyanogen OS and will also be included in CyanogenMod. It's more or less a complete messaging solution. It'll handle SMS, MMS, and Group messages. Additionally, it'll also provide integration to their WhispherPush service which will be getting relaunched. On the Cyanogen OS side, users will be able to use the TrueCaller integration to view caller ID as well as block spammers.
The company has taken in feedback from their users, with surveys on Google+ and Facebook from last November. The redesign of the Messaging app will be done in a few phases, with the first phase being the base of the app, so the team can add more features easily. Cyanogen will be redesigning the entire messaging app, and it'll use quite a bit of material design as well.
Looking at the mock screenshots that the team has put together, the new messaging app looks a lot like Inbox from Google. Which isn't a bad thing. It includes swipe to delete in the message conversation list, as well as an in-message media player which works for attachments that are video or audio. That means you won't need to choose an app to play the video or audio attachment in. This should make the user experience much better, as you're not jumping through apps.
It's a great looking app, and we're definitely excited to see the finished product from the Cyanogen team. The Cyanogen team urges users to send them feedback, just hit the source link below, and you'll find their blog post where you can leave feedback in the comments. Hopefully the header color is able to be customized by the user. The Cyanogen team seems to be hard at work, it'll be interesting to see what other kinds of goodies they have for us.