One of the problems in developing applications for mobile devices is the range of different environments and language you need to master. Any thing reduces this tower of babel and allows you to use what you already know must be a good idea. Enter - MonoDroid which allows .NET programmers to create apps for Android phones.
MonoDroid is a .NET development system targeting the Android mobile platform based on the Mono project's MonoTouch tool. Mono is all about porting .NET to other environments - Linux, OS X and so on and even Windows. MonoTouch is a development environment for the iPhone which uses the .NET Framework and languages. At the moment it represents the only non-Apple way of creating apps for the iPhone and iOS 4 in general. So far Apple don't seem to have found a way to object to its use or perhaps they just don't see it as a major development route. You still need a Mac and the iPhone SDK to use MonoTouch.
MonoDroid is a similar .NET based mobile development system but targeting the comparatively open Android environment. Currently Windows Phone 7 is the only mobile platform other than the iPhone/MonoTouch system that .NET programmers can target.
MonoDroid is about to enter beta testing and you can sign up for the test program at http://www.go-mono.com/monodroid/.
A release sometime later this year looks fairly certain and although it is based on the Mono open source project it will be a commercial product. MonoTouch costs $399 for the entry level Professional edition and $999 and $3,999 for the Corporate and 5 Corporate licence version. A trial version is available which isn't time limited but only allows deployment to an iPhone simulator.
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