When comparing Roundcube vs RainLoop, the Slant community recommends Roundcube for most people. In the question“What are the best self-hosted webmail clients?” Roundcube is ranked 1st while RainLoop is ranked 2nd. The most important reason people chose Roundcube is:
Licensed under GPL v3 with code available on [GitHub](https://github.com/roundcube/roundcubemail).
Ranked in these QuestionsQuestion Ranking
Pro Free and open source
Licensed under GPL v3 with code available on GitHub.
Roundcube is available in over 70 languages.
Pro Built-in caching
Roundcube caches messages to allow quicker access to your mailbox and to alleviate the strain put on the server. You can turn off caching (change 'enable_caching' property in your config/main.inc.php file) if you need messages to appear instantly.
Pro Sophisticated address book
Each contact can have their e-mail address, phone number, location, photos and associated URLs added to them. You can then group contacts and address your mails to the group instead of having to enter each person separately. Additionally, you can import vCards and CSV files as contact information. And, it has LDAP connectors.
Pro Plug-in support
Pro Drag & drop support
Roundcube supports attaching files simply by dragging and dropping them in.
Pro Access control support
Roundcube has built-in support for access control lists (ACL).
Has auto-refresh functionality for email boxes.
Pro Good documentation
You have access to the documentation for APIs as well plugins development.
Pro Spell checking
You can enable/disable spellcheck by changing "enable_spellcheck" in main.inc.php file.
Pro No database backend (except for contacts)
Except for contacts (which are optional), RainLoop does not require a database to run, allowing for easier management and configuration.
Pro Two-factor authentication
Pro Client-side OpenPGP
RainLoop supports an easy to use client-side OpenPGP encryption. It allows setting up, importing and generating keys from the admin panel. OpenPGP keys are stored in the browser's local storage.
Pro Social network authentication
RainLoop integrates with Facebook, Google, and Twitter for authentication. You can find out how to set up each of the services here.
Pro Easy to apply your own branding
Not only can you change the title, description and logo with a simple form in the admin panel, you can also completely customize the look of the login screen by supplying your own custom stylesheet.
Pro Keyboard shortcuts
Pro Configurable multi-level caching system
RainLoop caches messages to allow quicker access to your mailbox and to alleviate the strain put on the server. You can choose to disable it completely if you don't want it. Or, you can configure cache settings such as an additional caching key, browser-level cache, caching message user IDs while searching, etc. Even changing memcache hosts and ports and caching system data is possible.
Pro Dropbox integration
RainLoop allows attaching files from Dropbox. To enable this feature, go to Dropbox's developer apps page to register your app. You'll receive the app key value to enter in the admin panel.
Pro Drag & drop support
RainLoop supports attaching files simply by dragging and dropping them in.
Pro Plugin support
RainLoop has an easy to use plugin system. You can find the full list of plugins in the admin panel (or see their code on GitHub). From the admin panel, you can, in a simple, user-friendly way, manage them - install, uninstall, update. Unfortunately, a number of plugins and the related documentation, currently, is somewhat lacking.
Pro Easy to update
RainLoop can be updated from the admin panel. It does not require manually downloading, overwriting or configuring anything with each update.
Pro Free for personal and non-profit use
RainLoop is licensed under Creative Commons. Commercial use costs $85/yr.
Pro RainLoop plus Xeams
Complimented modern user interface to deliver mail from Xeams. Setting up both applications takes less than an hour on private server.
Pro Add multiple accounts
You can add multiple accounts and switch between them.
Pro Good UI
Good UI make it a pleasing experience
Not easy to create your own themes.
Con Extremely clunky unintuitive interface
For example the mouse cursor may start getting stuck and lag.
Con You can't make multiple accounts
It is not possible to make more then one account.
Con Search option are limited
You can only search for one item at a time instead of multiple search terms, which makes it difficult to go through large amounts of emails.
Unfortunately, all interfaces of roundcube look very old. I hope there will be a progress soon, Google Mail and Outlook Webmail should be the role models here. But also Yahoo mail offers an intuitive design.
If this open source software should survive, it must be completely renewed and bring up to new standards.
Con Lack of API documentation
Most "closed" open source ever seen.
Con No unified account view
Con Lack of documentation on plugin development
RainLoop sends the user to a plugin example that is nonexistent (which they state will be filled in later), which means the user has to figure out what the process is on their own.
Con Small community
No community forums, etc. This makes it difficult to find community help or just discuss techniques.
Con Questionable start
The developer created RainLoop while working at AfterLogic. You can read more about it here.
Con Raises security concerns since it's written in PHP
The language itself and the library ecosystem has a bad security track record.