Google’s Nexus 7 tablet has a great success even though with out expandable memory, rear camera etc. Your Nexus 7 Tablet has a front-facing camera but you cannot open camera directly, and you can use camera with apps like Google Plus, Skype, Facebook, Instagram etc. There is an app for launching camera.
Camera Launcher for Nexus 7
This Camera launcher for Nexus 7 app lets you access the front-facing camera on Nexus 7 like your are accessing on any other Android device through camera app. Go to Google Play Store and download Camera Launcher for Nexus 7. Once you installed the app, you can see the familiar camera icon in the apps list. Just tap the app to take photos, videos and even panoramic photos. But its quite difficult to take photos like you take using your other devices rear camera.