Is Android "open" enough to let you disable built-in features such as Phone book etc?

Is it possible in Android, to disable s开发者_如何学Gotandard features of the phone such as Mail, browser, phone etc?

What I'm asking is, is it possible to create an application that, when launched on startup provides some features to the user, but sits "on top" of android so they only have access to your application and not the underlying features of android itself?

Effectively, the phone still runs android, but the user never gets to see this as they are limited to the functionality that your app provides.

You can replace all of the stock apps that come in the AOSP. browser, dialer, homescreen, etc are all just APK files you could replace them with any other APK file you want, lots of ROMS from the Android mod scene replace the stock apps for more robust versions.