received a point for encryption during transit, but lost points because communications are not encrypted with a key to which the provider has no access, i.e., the communications are not end-to-end encrypted, users can't verify contacts' identities, past messages are not secure if the encryption keys are stolen, (i.e., the service does not provide forward secrecy), the code is not open to independent review, i.e., the code is not open-source), the security design is not properly documented, and there has not been a recent independent security audit. BlackBerry Messenger, Ebuddy XMS, Hushmail, Kik Messenger, Skype, Viber, and Yahoo! Messenger also scored one out of seven points. See also Comparison of cross-platform instant messaging clients List of defunct instant messaging platforms References External links 1997 software Android (operating system) software Instant Messenger BlackBerry software Classic Mac OS instant messaging clients Computer-related introductions in 1997 Cross-platform software Defunct instant messaging clients Instant messaging clients Internet properties disestablished in 2017 IOS software MacOS instant messaging clients Online chat Symbian software Unix instant messaging clients Videotelephony Windows instant messaging clients