But how come WhatsApp is/was supported in cm themes? I've always been theming WhatsApp on cm 12 and 13 on my old devices. (I don't know about cm14)Great suggestions! Theming other apps though is a challenge most of the time unless it's built into the app. The only good way to do it is to include things like whatsapp in the rom, but that requires getting permissions and then source code to insert the theme code. Just as an example, Whatsapp is owned by Facebook. Getting permission from them to include it in a rom would be pretty close to impossible IMO.