When it comes to mobile phone operating systems, many people believe that Google will triumph over Apple with Android - simply because the big G's OS is a lot more open.

And now, it is even more open with the launch of App Inventor - the free do-it-yourself app designing software that Google will hope opens up app development to everyone, and not just those people with a knowledge of programming and coding.

The software has been in development for around a year now, and Google has been testing it on a number of non-techy-types including high school girls, undergrad students not reading computer science and trainee-nurses.

The results have included an app designed by students that fired off a text if the phone's owner fell over (using the accelerometer's sensor), and also an app designed to auto-reply via text to let people know if you were driving when they tried to contact you.

The software uses an image friendly UI that allows for a dragging and dropping of code in the form of blocks. The theory is you build your app block-by-block, a bit like a Lego construction.

“The goal is to enable people to become creators, not just consumers, in this mobile world”, said Harold Abelson, a computer scientist at the MIT, who is leading the project for Google. “We could only have done this because Android’s architecture is so open”.

The software is web-based predominately - you can sign up using your existing Google account. When making programs, an Android phone must be connected to a computer via USB.

The launch comes as reports suggest that the Android Marketplace is on course to register its 100,000th app - possibly as soon as this month - meaning a growth of around 75,000 in just 6 months.

With tools like the App Inventor now available, it surely won't be long before Android catches the App Store up. (The latest figures estimate that there are 225,000 apps available for iPhone users.)

Are you an Android fan? If so, give App Inventor a spin and let us know how you get on. Check out the guide video below as well, which gives a quick overview as to how it all works: