Consumer rights covering products such as cars and white goods are to be extended to apps and music downloads in a consumer bill of rights to be unveiled in the Queen's speech on Wednesday.

Jo Swinson, the consumer minister, said the government would update the law to make it "fit for the 21st century" by ensuring consumers can secure refunds or replacements if web-based products fail.

The Department for Business, Innovation and Skills estimates that the changes could save up to £4bn over 10 years by consolidating consumer rights in one place. These are currently split between eight pieces of legislation while powers giving trading standards officers the ability to investigate breaches of consumer law are spread across 60 pieces of legislation.

The changes will lead to:

• An updating of the law to give greater protection to consumers who download films, music and games – a £1bn industry. The bill will make clear that a consumer must receive a refund if an online game freezes or if a film stream is unwatchable even if the broadband connection is fine.

• New protections for consumers making it easier to apply for compensation for breaches of competition law and new powers for trading standards officers to seek court orders requiring compensation to be paid.

Swinson said: "Stronger consumer protection and clearer consumer rights will help create a fairer and stronger marketplace. We are fully aware that this area of law over the years has become unnecessarily complicated and too confusing, with many people not sure where to turn if they have a problem. We are hoping to bring in a number of changes to improve consumer confidence and make sure the law is fit for the 21st century."

Richard Lloyd, executive director of the consumer rights organisation Which?, said: "A consumer bill of rights is a welcome step towards ensuring that we have consumer laws fit for the 21st century. This bill is about making it easier for people to understand their rights and giving consumers power to challenge bad practice. It should also mean that both consumers and regulators have the tools they need to challenge unscrupulous businesses that breach the law.

"There are many welcome proposals in this bill, including extending the power of collective redress in competition cases and reforming the law on unfair terms and conditions. We urge the government to go further and to extend civil remedy powers to allow private enforcement bodies, like Which?, to take action against rogue companies and force them to put things right for consumers."