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 UOM values.
Tap the save button to the left of the row to save the current conversions.
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.