Version 3 of CALC 1 is now available. Due to the changes in version 3 we to not make it an update to version 2, This is due to the changes that needed to be make to the database that stores your calculators, some which may be customized.
Version 2 owners should look for the CALC 1 Bundle and "Complete the Bundle" to get version 3.
So there is no reason to purchase this version. It only is still on the store to give existing owners a way to upgrade to the new version.