Over the last few days the 50p, £2 and £20 note sections of the website have been updated with the current coins (and new £20). Many images have also been improved. These changes (and more) will soon be reflected in the app.
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.