COI - Chat Over IMAP

Skip to main content

COI - Chat Over IMAP - is a universal chat protocol that is Free, Open, Easy, Safe and does not require developers to build or maintain a server.
COI uses an email address and any IMAP server as its infrastructure. This means it can already connect 3.8 billion users - anyone with an email address.
Developers can now concentrate on building clients for any device, in any language (Java, Swift, JavaScript, Dart, Kotlin, etc.), and let COI handle the communication.

Only COI will overcome the current messaging silos and allow everyone to compete on the same terms. 

Most popular messaging services are currently proprietary, closed and operated by single providers. This leads to several problems:

  • The provider knows all about your social network: when you communicate with whom, the frequency of your communication and the number, type and length of your messages – even with end to end encryption in place.

  • Service providers depend on the rules set by the messaging owner and access to the API for participation. If the messaging provider changes the rules or API, you are out of luck and must adapt fast.

  • Users cannot simply change to another provider; all their friends and peers are on that popular service. If they want to switch, they would need to convince all their friends to join the new service too. Other side effects are they would lose all their conversation history, if they dare to move away. Also, if you don’t like the new app version? Bad luck, you cannot go anywhere else!

  • Each network is closed and the users in that network are isolated. This means restricted movement between silos, no new innovation outside the controlling power, no new players, no resistance to attacks (single source code) and it simply goes against the philosophy of the internet: freedom, innovation and growth around the use of common standards.

  • The network is only controlled by a single party, you cannot start hosting your own WhatsApp, WeChat or FB Messenger Service.

  • Some large providers, like Facebook, control many of the popular messaging apps, like WhatsApp and Facebook Messenger making it feel like there is no real choice.

Maybe you are thinking “I thought this is why we have Signal, Telegram and the other privacy-centric apps?” – they might very well be better than some of the more popular networks, but in the end, they control the network and other providers are locked out. Basically, you are exchanging one silo with another. 

What about XMPP and” – glad you asked! We love XMPP and, because they provide a great solution, but this only solves the problem in theory though. With XMPP and -based services you would still need to convince everyone to join your new network. Easy in theory, very complex in practice! 

What about RCS?“ – Most notably, RCS requires a device to have a phone number (MSISDN). As communication is quickly migrating towards pure IP based solutions, MSISDNs become a relics of the past. Most new innovative devices come without MSISDNs, e.g. voice enabled devices such as smart speakers, VR and AR devices, portable game consoles, etc. With this dependency on MSISDNs, RCS’ future is uncertain. Additionally, operators already have wasted millions with RCS, so they are hesitant when being asked to spend further millions on this technology. Last but not least, Apple does not support RCS out of the box at the moment, as they successfully operate a proprietary messaging service.

Fundamentally, COI is a free & open standard that is built on top of the IMAP and SMTP standards. 
The COI ecosystem is the COI Standard plus compatible Client Apps and Email Servers.
COI works with all email severs, but IMAP servers can be enhanced with extra COI capability. These extra capabilities make the development of both services and applications much easier and more powerful.

Free & Open RFC Standard

  1. COI first starts by connecting to an IMAP server.
  2. After checking for server compatibility it then uses this connection, and an email address, to communicate to someone.
  3. If the recipient has a COI client then communication continues as chat, if not then messages are received as emails.

Since this is all based on email, you can communicate with users even when they do not have COI-compatible servers or apps.

Why Email?

With COI you have all your messages in one place – both emails and chat messages. This means that you can also easily find your information again when searching for messages. You can also reach everyone, there are more than double active email users than WhatsApp users, for example. Only with COI you can choose your preferred communication provider. You can also switch your provider, if you are not satisfied anymore. This is not possible with privacy centric but closed service offerings such as Signal, Telegram or similar.

Don’t trust anyone? With projects such as The Helm you can even run your own email service in your home!

Same like with your email service provider, COI offers you a selection of compatible apps to choose from – again, this freedom of choice is crucial for being able to select the COI client app that you can trust and that you like.

Last but not least, every COI client app can offer a variety of end to end encryption options to keep your communication absolutely private.

COI for Developers

COI is the only ecosystem that provides openness, a strong messaging basis AND overcomes the network effect. With COI you don’t need to develop, host and maintain your own communication servers. Thanks to Delta Chat Core, as a client developer you do not even need to deal with IMAP directly.

COI is based on the firm belief that only a free and open standard provide a basis for prosperity and freedom for everyone. Please review our current draft of the COI standard RFC (“request for comments”) at the developer wiki.

COI for ISVs and Partners

Only COI provides and open ecosystem that is not controlled by a single player. This allows you to rely on your investments and nobody can forbid you to provide your services in this open ecosystem. Email has been scrutinized heavily over the years, so there won’t be bad legal surprises.

As an independent software vendor (ISV) you can choose between different integration options, for example: COI compatible client apps, Integrations into COI apps, COI compatible IMAP and SMTP servers, Email-based services like bots

By offering COI compatible chat services you can rejuvenate your audience and increase usage of your services. This obviously brings in new monetization options like advertisement, affiliate and upsell offerings. For businesses you can offer a unified messaging system, in which all messages are in one place. If you combine messaging with full governance, compliance and archiving, you will solve a lot of current problems of your business customers.

Due to the open nature of COI, you can even offer branded client apps and select from a variety of COI compatible vendors.

As a business you will already use email for your communication with customers, partners and within your company. With COI you will now additionally gain chat capabilities – and only with COI you can choose your preferred service provider or even host your COI email service on your premise.
With COI you can select your preferred messaging client provider and easily integrate your own services.

Sign up to the COI developers mailing list.

Sign up