When we wrote our book Pocket PC Development in the Enterprise back in 2001, one of our goals was to help developers with an architectural blueprint for building solid mobile multi-tier applications. At that time, most focus for mobile developers was on the user interface and the device side of the mobile solution.

Since then, a lot of things have changed. The Windows Mobile development platform with .NET Compact Framework as the foundation, has evolved into a very powerful offering to mobile developers. Technologies has constantly migrated from the desktop (full) framework, even if it sometimes seems too slow when one is eagerly waiting. Who else is eager to use LINQ to SQL with SQL Server Compact, full WCF support, or build mobile Silverlight applications?

But, some things remain the same, and one of these is the view on mobile solutions as being a part of a bigger whole. Almost no mobile applications live alone! In most cases, they are part of an integrated solution that extend existing business processes to reach further out in the hands of the employees. Therefore, a modern mobile architecture starts with a solid architecture on the server, and can be extended to support multiple channels (thin/rich clients, fixed/mobile devices, etc).

During the years since we wrote the book, the blueprint has evolved with the changes in technology. I say evolve, because most changes only meant that the architecture was upgraded to embrace the new technologies. Recently, however, some major changes has occurred that force some more drastic changes to the architecture. The most significant are LINQ (specifically LINQ to SQL and the upcoming ADO.NET Entity Framework), WCF, and Silverlight. The observant reader notes that these technologies span the whole architecture spectrum from data access, via communcation links to UX. In addition to these, there are also a number of enhancements for the mobile developer that spice up an architecture that in addition to support traditional clients, it also needs to support mobile clients as well.

As you will see, when we move forward in this series of blog posts, I'm a big fan of the KISS principle. Therefore, the primary goal is to keep things as simple as possible to minimize the learning curve while at the same time still create a valid architecture that is easy to implement, test, and maintain.

In upcoming posts, I will continue with more of my thoughts on the changes in architecture in general and more specifically on architectures that suite mobile solutions.