Not only cross platform but cross service.  The real loss in messaging in general is the lack of interoperability.  One thing email did get right - protocols.  The messaging wold seems to have given up on this to hoard and lock in users to silo&#x27;d messaging systems - wechat, snapchat, fb messenger, etc.  How powerful would it be for people to have the ability to send messages across these systems <i>with</i> the support of these vendors (as opposed to the Trillian like solutions of the prior decade).