In our experience these are some of the most effective and keenest priced mobile, tablet and DVD aids:
This all in one app covers both theory and hazard perception:
There are free trial versions to try before you buy.
These books and DVDs are all available from Amazon:
Get a copy of the highway code. It's the most important guide to driving, is a massive help for the theory test, and is only £2.50 - or less. To quote the publisher:
"All road users have a responsibility to keep their knowledge up-to-date, so make sure you do just that with the latest edition of this handy reference guide. Every day, on average, five people are killed and 60 people are seriously injured on our roads. If we're to bring those figures down, it's vital that all road users - drivers, motorcyclists, cyclists, horse riders and pedestrians - are familiar with all the rules in The Official Highway Code."
If you want a "proper" theory test book - this is the one:
"The official theory test book for car drivers, compiled by the Driver and Vehicle Standards Agency. It contains multiple choice questions from the whole theory test question bank, with answers and explanations, dealing with topics such as: alertness and attitude, vehicle safety and handling, safety margins, hazard awareness, vulnerable road users, motorway rules and rules of the road, road and traffic signs, documents, accidents, and vehicle loading."
This DVD is for your Windows PC:
"Theory test - every official DVSA revision question, answers and explanations, for learner drivers, motorcyclists and trainee driving instructors. Hazard Perception Test - sit unlimited mock tests using interactive CGI and high definition video clips."
A DVD for any DVD player:
"Plays on any dvd compatible device including: dvd player, xbox 360/xbox one, ps3/ps4, pc/mac. Theory test - all the latest official dvsa revision questions for learner drivers and motorcyclists. Hazard perception test - sit hundreds of interactive mock tests and watch the official CGI sample video clips."
"Updated and redesigned, this is THE industry-standard driving manual. It is focussed on you, the driver, and explains how to get the most enjoyment from your driving with the correct attitude, behaviour and skills. The Official DSA Guide to Driving - the essential skills, together with The Official Highway Code and Know Your Traffic Signs, provides the source material for learner car driver and driving instructor theory tests, being referenced throughout with the latest official DSA theory test titles for car drivers."
"Better Driving will help you to improve your driving and boost your confidence. Discover how emotions, attitude and behaviour can affect your driving. Learn how to manage stress and anxiety through real-life scenarios and test-yourself questionnaires."
Finally, this is the police driver's bible:
"The new edition of this iconic publication - prepared through close consultation with the police, other emergency services and driving instructors - has been fully revised and updated to give the best evidence-based and authoritative guidance on advanced driving skills. It is an essential text not just for police drivers, but for anyone who wants to become a better, safer driver. Key features: Become a better driver - the techniques outlined in Roadcraft will help you become a safer and more skilful driver in the most demanding situations. Be safer on the road - with a focus on self-assessment, the Roadcraft system of car control provides you with a systematic decision-making tool that enables you to deal with hazards and respond to new ones safely and efficiently. Learn new skills - new full colour 3D illustrations help you learn key principles and techniques for better driving. Expert guidance - with input from trainers in the emergency services, Roadcraft is recognised internationally as the gold standard for driving. It includes new chapters on manoeuvring at low speeds and on techniques for emergency response driving."