The London Beth Din Kashrut Division provides all you need to know about Kashrut
It works through its website kosher.org.uk, allows you to purchase the Really Jewish Food Guide, in book form, and there is also an App available from the iTunes Store or Google Play. You can subscribe to updates, and look up to see whether a specific product is kosher or not. You can even suscribe to receive updates by text.
Text ‘KOSHER’ to 07786-200350 to sign up for free Kashrut alerts by text.