* Quick guide (touch right upper corner to show)
* In iPad, the quick guide is shown all the time in vertical orientation, and it can be scrolled in horizontal orientation.
* Copy to clipboard (touch left upper corner to copy)
* American, European and Indian decimal separators (touch ON to open Settings)
* Visual feedback for typing
* Audible feedback (touch ON to open Settings)
* Save memory to iCloud
* Vertical layout. Orientation can change with phone's rotation or stay fixed.