Possible Duplicate:
Is there a way to develop android applications on the device?
Is there any way by which an Android device (preferably tablet with ICS) be used for Apps development? What advantage does google nexus have for the developers?
Possible Duplicate:
Is there a way to develop android applications on the device?
Is there any way by which an Android device (preferably tablet with ICS) be used for Apps development? What advantage does google nexus have for the developers?
Yes. With ADB you can debug apps on the Android device from your PC.
If you meant writing an app on the device directly, I have seen apps that allow you to write and run Java as apps, but I can't imagine anyone making high-quality apps with something like this. I would avoid it and use Eclipse.
One advantage of the Nexus devices is supposed to be that it is "stock" Android-- without the weird junk like Touchwiz and Sense UI. Testing on stock would result in an app more likely to work across the other flavors of Android. The Galaxy Nexus had some extra stuff on it, but I can't remember what.
Another advantage is that the Nexus devices are supposed to get updates direct from Google without having to wait for carriers and manufacturers to modify the new versions before pushing them out.