An application for online answer engine Wolfram Alpha apparently is a big hit with iPhone users. Here's an email we received today from the Wolfram Alpha team:

We are happy to announce that the Wolfram|Alpha App for the iPhone and iPod touch popped up on the App Store's "What's Hot" list today. We are delighted that Apple selected the app to be featured, recognizing the intense interest and excitement being shown in Wolfram|Alpha.

We were pleasantly surprised, too, to see the Wolfram|Alpha App appear on the store's "Top Grossing" list on the second day it was available and remain there through the week. We've also been thrilled by the positive feedback from those who have purchased the app, visible in the reviews on the App Store.

If you haven't seen the app yet, check it out: http://products.wolframalpha.com/iphone