When you are in the inAppBrowser plugin you cannot use any of the other Cordova plugins, because that plugin is a way to provide external web viewing. See the previous post for some more background -- you are NOT writing code in a browser, you are writing code in an HTML5 interpreter known as a "webview." Please search the web for articles regarding "how does a Cordova PhoneGap app differ from a browser web app" or something like that for more background on the differences between a web app that runs in a browser and a web app that runs in a Cordova webview.
