AIM was an instant messaging and presence computer program created by AOL, which used the proprietary OSCAR instant messaging protocol and the TOC protocol to allow registered users to communicate in real time.
Instant messaging (IM) technology is a type of synchronous computer-mediated communication involving the immediate (real-time) transmission of messages between two or more parties over the Internet or another computer network. Originally involving simple text message exchanges, modern IM applications and services tend to also feature the exchange of multimedia, emojis, file transfer, VoIP, and video chat capabilities.
A software development kit (SDK) is a collection of software development tools in one installable package. They facilitate the creation of applications by having a compiler, debugger and sometimes a software framework. They are normally specific to a hardware platform and operating system combination. To create applications with advanced functionalities such as advertisements, push notifications, etc; most application software developers use specific software development kits.
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.
End-to-end encryption (E2EE) is a private communication system in which only communicating users can participate. As such, no one else, including the communication system provider, telecom providers, Internet providers or malicious actors, can access the cryptographic keys needed to converse. End-to-end encryption is intended to prevent data being read or secretly modified, other than by the true sender and recipient(s). The messages are encrypted by the sender but the third party does not have a means to decrypt them, and stores them encrypted. The recipients retrieve the encrypted data and decrypt it themselves. Because no third parties can decipher the data being communicated or stored, for example, companies that provide end-to-end encryption are unable to hand over texts of their customers' messages to the authorities.
iOS is a mobile operating system developed by Apple exclusively for its devices. It was unveiled in January 2007 for the first-generation iPhone, which launched in June 2007. Major versions of iOS are released annually; the current stable version, iOS 18, was released to the public on September 16, 2024.
The iOS SDK, formerly the iPhone SDK, is a software development kit (SDK) developed by Apple Inc. The kit allows for the development of mobile apps on Apple's iOS and iPadOS operating systems.
Wickr is an American software company based in New York City. It is known for its instant messaging application of the same name. The Wickr instant messaging apps allow users to exchange end-to-end encrypted and content-expiring messages, and are designed for iOS, Android, Mac, Windows, and Linux operating systems. Wickr was acquired by Amazon Web Services (AWS) in mid-2021. The free version of the app was discontinued in December 2023.
ChatSecure is a messaging application for iOS which allows OTR and OMEMO encryption for the XMPP protocol. ChatSecure is free and open source software available under the GPL-3.0-or-later license.
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.
Wire Swiss GmbH is a software company with headquarters in Zug, Switzerland. Its development center is in Berlin, Germany. The company is best known for its messaging application called Wire.
Signal is an open-source, 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.
Matrix is an open standard and communication protocol for real-time communication. It aims to make real-time communication work seamlessly between different service providers, in the way that standard Simple Mail Transfer Protocol email currently does for store-and-forward email service, by allowing users with accounts at one communications service provider to communicate with users of a different service provider via online chat, voice over IP, and videotelephony. It therefore serves a similar purpose to protocols like XMPP, but is not based on any existing communication protocol.
Peerio was a cross-platform end-to-end encrypted application that provided secure messaging, file sharing, and cloud file storage. Peerio was available as an application for iOS, Android, macOS, Windows, and Linux. Peerio (Legacy) was originally released on 14 January 2015, and was replaced by Peerio 2 on 15 June 2017. The app is discontinued.
Firebase Cloud Messaging (FCM), formerly known as Google Cloud Messaging (GCM), is a cross-platform cloud service for messages and notifications for Android, iOS, and web applications, which as of May 2023 can be used at no cost. Firebase Cloud Messaging allows third-party application developers to send notifications or messages from servers hosted by FCM to users of the platform or end users.
Wire is an encrypted communication and collaboration app created by Wire Swiss. It is available for iOS, Android, Windows, macOS, Linux, and web browsers such as Firefox. Wire offers a collaboration suite featuring messenger, voice calls, video calls, conference calls, file-sharing, and external collaboration – all protected by a secure end-to-end-encryption. Wire offers three solutions built on its security technology: Wire Pro – which offers Wire's collaboration feature for businesses, Wire Enterprise – includes Wire Pro capabilities with added features for large-scale or regulated organizations, and Wire Red – the on-demand crisis collaboration suite. They also offer Wire Personal, which is a secure messaging app for personal use.
Element is a free and open-source software instant messaging client implementing the Matrix protocol.
