It depends on the type of company.
If most of your users are working off-site and you have only a basic ADSL then one of our local or international partners can provide you with your hosted version. It will cost the same as other fully featured "Cloud" services but at least you'll own your data and can easily migrate the entire Zarafa infrastructure, very easily, on-site or to another provider.
If you have most of your users in your main office and/or you have business grade connectivity then it makes sense to keep the traffic local. Even if you want to keep you local infrastructure as lean as possible you'll need a firewall and a local storage. In that case running Zarafa on the same box as the firewall or the storage or combine everything in one low cost solution is very efficient and secure. SMBs may find the Collax Business Server, which integrates Zarafa, a perfect solution for their needs.
Then we are sure that you'll fall in love with Zarafa WebApp as you'll get the Outlook features you need in a web browser.
You can use any device you like as long as you have connectivity if you wish to use Zarafa WebApp. Most of the other devices will synchronise natively with Zarafa as it's seen as a Microsoft Exchange server so you'll be able to work both on-line and off-line.
Like most of the solutions on this web site, Zarafa, is based on Open Source technologies but Zarafa is also the name of the company that develops the product and guarantees the quality, the support and the development of the enterprise features your organisation require.
Zarafa is also a bit yours as, apart from the commercial version, they release free Community versions and provide patches and feedbacks to the Open Source community in general.
Zarafa releases a Community version that you can use and you can ask the community if you need support.
If you are already paying Microsoft a considerable amount of money for the privilege of using Outlook or Active Directory, with which Zarafa seamlessly integrates, then we are sure you will not mind supporting Zarafa with a very small maintenance fee.
If you consider the savings in licensing, the low hardware requirements and the possibility of finally integrating your communication platform with the rest of your applications then you'll see that Zarafa will be yours practically for free.
Zarafa is not a new start-up from Silicon Valley, it's a well established privately owned Dutch company that started in 2005 with the precise intent to develop an alternative to MS Exchange. Over the years it has kept its focus and it kept providing what is today not just the best alternative to MS Exchange but a better solution than Cloud offerings.