It is certainly doable. I haven't done it myself, but I know of people who have done it successfully on Android.

Unfortunately, I don't think Phonegap is a very good solution. Depending on your application, it may be good enough, but it's overall not as good as true native development.

It is not. Not as a general purpose solution anyway. Phonegap can be useful in order to quickly publish a very simple application on both platforms. Outside of that, its disadvantages pile up VERY quickly.