BlackBerry Enterprise Messenger is the preferred method (PIN in barcode below. Click to enlarge). Alternatively please use the form below.
BlackBerry Enterprise Messenger can be downloaded on iOS and Android. Once an account has been set up, you can then install on Windows and macOS. For more information: BBMe
I don't 'slack' in my approach to security, nor do I use 'slack' - so please don't ask.
Alternatives: ICQ: 219-620 or XMPP. PGP Key