The Oracle Application Express (APEX) development team hit the ball out the park again with some of the new features you find in APEX 4.1 Early Adopter 2!
tryapexnow.com got updated last night with a new version of APEX and I just played a little bit with it. Two new features caught my eye: the data load wizard and the drag/drop in the calendar.
Drag/Drop in Calendar
I followed the wizard to create a new page of type Calendar and it now asks if you want to enable Drag and Drop.

The drag and drop features uses an On Demand Page Process which you have to select in the Calendar Attributes. If you click on the Process label you see an example how such a Process needs to look like.

Data Loading Pages (wizard)
You want to allow people to upload data in your application (using copy/paste or a csv file)? Now you just have to follow the Data Loading wizard and it does everything for you. It even includes a mechanism that detects if it needs to do an update or an insert, it allows you to add data transformations and validations and it just flows well.
When you finish the wizard the page in you application looks like this

Many features that come with this wizard, really nice. And it's just an APEX page, so you can still customise it like you want.
If you didn't try APEX 4.1 yet, give it a go, it's worth to see what's coming... and remember to use the Feedback link to give the APEX development team feedback.