The landscape for instant messaging involves cross-platform instant messaging clients that can handle one or multiple protocols. Clients that use the same protocol can typically federate and talk to one another. The following table compares general and technical information for cross-platform instant messaging clients in active development, each of which have their own article that provide further information.
Mobile device management (MDM) is the administration of mobile devices, such as smartphones, tablet computers, and laptops. MDM is usually implemented with the use of a third-party product that has management features for particular vendors of mobile devices. Though closely related to Enterprise Mobility Management and Unified Endpoint Management, MDM differs slightly from both: unlike MDM, EMM includes mobile information management, BYOD, mobile application management and mobile content management, whereas UEM provides device management for endpoints like desktops, printers, IoT devices, and wearables as well.
Andrew "bunnie" Huang is an American researcher and hacker, who holds a Ph.D in electrical engineering from MIT and is the author of the freely available 2003 book Hacking the Xbox: An Introduction to Reverse Engineering. As of 2012 he resides in Singapore. Huang is a member of the Zeta Beta Tau fraternity, and a resident advisor and mentor to hardware startups at HAX, an early stage hardware accelerator and venture capital firm.
iOS jailbreaking is the use of a privilege escalation exploit to remove software restrictions imposed by Apple on devices running iOS and iOS-based operating systems. It is typically done through a series of kernel patches. A jailbroken device typically permits root access within the operating system and provides the right to install software unavailable through the App Store. Different devices and versions are exploited with a variety of tools. Apple views jailbreaking as a violation of the end-user license agreement and strongly cautions device owners not to try to achieve root access through the exploitation of vulnerabilities.
Multi-factor authentication is an electronic authentication method in which a user is granted access to a website or application only after successfully presenting two or more pieces of evidence to an authentication mechanism. MFA protects personal data—which may include personal identification or financial assets—from being accessed by an unauthorized third party that may have been able to discover, for example, a single password.
ClockworkMod is a software company, owned by Koushik "Koush" Dutta, which develops various software products for Android smartphones and tablets. The company is primarily known for its custom recovery image, ClockworkMod Recovery, which is used in many custom ROMs.
The Guardian Project is a global collective of software developers, designers, advocates, activists, and trainers who develop open-source mobile security software and operating system enhancements. They also create customized mobile devices to help individuals communicate more freely and protect themselves from intrusion and monitoring. The effort specifically focuses on users who live or work in high-risk situations and who often face constant surveillance and intrusion attempts into their mobile devices and communication streams.
WARRIOR PRIDE is the GCHQ and NSA code name for a pair of spyware kits that can be installed on the iPhone and Android-based smartphones. Information about these kits was published by the press on 27 January 2014 from the documents leaked by Edward Snowden.
TextSecure was an encrypted messaging application for Android that was developed from 2010 to 2015. It was a predecessor to Signal and the first application to use the Signal Protocol, which has since been implemented into WhatsApp and other applications. TextSecure used end-to-end encryption to secure the transmission of text messages, group messages, attachments and media messages to other TextSecure users.
Open Whisper Systems was a software development group that was founded by Moxie Marlinspike in 2013. The group picked up the open source development of TextSecure and RedPhone, and was later responsible for starting the development of the Signal Protocol and the Signal messaging app. In 2018, Signal Messenger was incorporated as an LLC by Moxie Marlinspike and Brian Acton and then rolled under the independent 501c3 non-profit Signal Technology Foundation. Today, the Signal app is developed by Signal Messenger LLC, which is funded by the Signal Technology Foundation.
Threema is a paid cross-platform encrypted instant messaging app developed by Threema GmbH in Switzerland and launched in 2012. The service operates on a decentralized architecture and offers end-to-end encryption. Users can make voice and video calls, send photos, files, and voice notes, share locations, and make groups. Unlike many other popular secure messaging apps, Threema does not require phone numbers or email addresses for registration, only a one-time purchase that can be paid via an app store or anonymously with Bitcoin or cash.
mysms is a cross-platform text messaging service, based on Short Message Service (SMS), for smartphones, tablet computers, and laptop and desktop personal computers.
Signal is an encrypted messaging service for instant messaging, voice calls, and video calls. The instant messaging function includes sending text, voice notes, images, videos, and other files. Communication may be one-to-one between users or may involve group messaging.
Eddystone was a Bluetooth Low Energy beacon profile released by Google in July 2015. In December 2018 Google stopped delivering both Eddystone and Physical Web beacon notifications. The Apache 2.0-licensed, cross-platform, and versioned profile contained several frame types, including Eddystone-UID, Eddystone-URL, and Eddystone-TLM. Eddystone-URL was used by the Physical Web project, whereas Eddystone-UID was typically used by native apps on a user's device, including Google's first party apps such as Google Maps.
In cryptography, the Double Ratchet Algorithm is a key management algorithm that was developed by Trevor Perrin and Moxie Marlinspike in 2013. It can be used as part of a cryptographic protocol to provide end-to-end encryption for instant messaging. After an initial key exchange it manages the ongoing renewal and maintenance of short-lived session keys. It combines a cryptographic so-called "ratchet" based on the Diffie–Hellman key exchange (DH) and a ratchet based on a key derivation function (KDF), such as a hash function, and is therefore called a double ratchet.
GrapheneOS is an Android-based, open source, privacy and security-focused mobile operating system for selected Google Pixel devices, including smartphones, tablets and foldables.
scrcpy is a free and open-source screen mirroring application that allows control of an Android device from a desktop computer. The software is developed by Genymobile SAS, a company which develops Android emulator Genymotion.
Conversations is a free software, instant messaging client application software for Android. It is largely based on recognized open standards such as the Extensible Messaging and Presence Protocol (XMPP) and Transport Layer Security (TLS).
