Skype is an instant messaging and VOIP (Voice Over Internet Protocol) client to communicate with people in a distant place.

Viber Free Messenger and Phone Calls.

Fring connects with Skype, MSN Messenger, ICQ and Google Talk from your iPhone.

Google Duo is a video chat mobile app available on the Android and iOS operating systems.

WhatsApp Messenger is an instant messaging platform owned by Facebook.

Yahoo! Messenger (sometimes abbreviated Y!M) is an advertisement-supported instant messaging client and associated protocol provided by Yahoo.

ooVoo is a video chat and an instant messaging client.

SightCall remote support software enables live video streaming and remote access on mobile devices and desktops for customer service and tech support.