The upgrade, which shows current values in used and as-new condition for all of the hundreds of coins contained within the app costs £3.99.
The February 2018 version of the app contains 1,1122 valuations, i.e. 561 different coin values in as-new and used condition.
The upgrade includes one year of free updates to the valuations, which are made usually once or twice a month.
The Check Your Change admin is Mr C H Perkins, publisher of numismatic publications in printed and eBook format. Author of "Collectors' Coins - Decimal Issues of the UK" and other books on British coins and related subjects.