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ianhanniballake is right. You can get all the functionality of
FragmentActivity. In fact,
FragmentActivity has more functionality).
FragmentActivity you can easily build
tab and swap format. For each tab you can use different
Fragments are reusable). So for any
FragmentActivity you can reuse the same
Still you can use
Activity for single pages like list down something and edit element of the list in next page.
Also remember to use
Activity if you are using
FragmentActivity if you are using
android.support.v4.app.Fragment. Never attach a
android.support.v4.app.Fragment to an
android.app.Activity, as this will cause an exception to be thrown.
FragmentActivity gives you all of the functionality of
Activity plus the ability to use Fragments which are very useful in many cases, particularly when working with the ActionBar, which is the best way to use Tabs in Android.
If you are only targeting Honeycomb (v11) or greater devices, then you can use
Activity and use the native Fragments introduced in v11 without issue.
FragmentActivity was built specifically as part of the Support Library to back port some of those useful features (such as Fragments) back to older devices.
I should also note that you’ll probably find the Backward Compatibility – Implementing Tabs training very helpful going forward.
If you use the Eclipse “New Android Project” wizard in a recent ADT bundle, you’ll automatically get tabs implemented as a Fragments. This makes the conversion of your application to the tablet format much easier in the future.
For simple single screen layouts you may still use