When you return to your Focused or Formula Calculator, the last "To Value" will now be in the x register. The last x value can be recalled using the RCL-last x.
The "Swap" button will swap the From and To UOMs.
Tapping one of the buttons in the "Saved Conversions" will load the conversion calculator with those currencies.
Tap the save button to the left of the row to save the current conversions.
The "Auto-Man" buttons allow you select how the currency rates will be updated. The reference rates are usually updated by 16:00 CET weekdays. See the link below for more details on the rates. There is a widget below to convert CET to local time.
The "As of:" date is the reference date of the rates. Tap the refresh button (next to the "Auto-Man button) for the latest available rates.
For the customizable version of CALC 1, there will be a "Create Key" button. Tapping this button will create a key and copy it to the clipboard. You can then paste the key on a calculator. See Copy and Paste keys for more information.