Start-ups may be small but they play a key role in the global economy through innovation and disruption of the status quo. And some are thriving even in the COVID-19 world. Click or scroll through to see the upstarts who are making it their business to challenge big business. All dollar figures in US dollars.

It may not seem like a newcomer but just six months ago Zoom was a little-known video conferencing app, with 10 million monthly users in December. By March, that figure had ballooned to 200 million monthly users. Zoom is now the leading video conferencing service in the US with a 42.8% market share, according to data from online investment publication LearnBonds. 

Bulb Energy is making waves in the UK energy industry by offering a single tariff with 100% renewable electricity and carbon neutral gas. Founded in 2015, it is now the nation's fastest-growing energy supplier and has more than 1.7 million customers. Bulb currently has 6% of the UK energy market, the largest share of any provider outside the 'Big Six' firms that make up the majority of domestic energy supply. The London-based company is now expanding to France, Spain and the US. 

Describing itself as a nutritionally-complete food powder, Huel claims to provide all the nutrients you need to live off. The company name is an amalgamation of "human fuel" and the company says it has sold more than 100 million meals, in the form of shakes and energy bars, since 2015. Its fortunes are in contrast to longer-established meal replacement drink firm Slimfast, which was bought by Glanbia for €302 million ($330m/£275m) in 2018 after posting a pre-tax loss of $12 million (£10m) for 2017. 

Lemonade is a New York-based start-up that is shaking up the wider insurance industry by using artificial intelligence to provide quotes and evaluate claims quickly and easily. The company is a licensed insurance provider in its own right, unlike other digital rivals, and enables customers to sign up for cover through a chatbot. Already available in 29 US states, Lemonade launched in Germany in the summer of 2019. After its latest IPO on 2 July, shares soared by 170% by close on 7 July and the company's valuation tripled to $4.46 billion (£3.5bn) in a matter of days. 

GoPuff is an online convenience store that promises to deliver snacks, drinks, ice cream and more at any time of the day or night. For a flat fee of just $1.95 (£1.60), the service will deliver any of 3,000+ products direct to your address. In the US, sales of fast-moving consumer goods (FMCG) represent 3% of GDP and GoPuff is a challenger to established businesses such as Instacart, Doordash and UberEats. GoPuff, which claims to be the digital convenience retailer, is available in more than 100 major cities across the US. 

Coda is taking on the software giants by offering a cloud-based document editor that is as powerful as an app. The San Francisco-based company's product combines the functionality of a traditional word-processing document with that of a spreadsheet, with the additional possibility of adding some third-party and basic programming functionalities. Apparently the founders settled on the name Coda because it's "a doc" backwards. 

Peloton is cashing in on increased demand for home exercise equipment as the pandemic has forced many gyms to shut. The New York-based company's service centres around its $2,245 (£2,025) Peloton Bike, which is used in combination with live-streamed and pre-recorded exercise classes broadcast on a 22-inch screen. During the pandemic, demand for Peloton bikes was so high that the company doubled its production in June and still couldn't keep up, while its share price rose 36.9%. The company is valued at $17.7 billion (£14bn) as of 9 July. 

Reducing traditional farming's vast demands for water and land, indoor farming start-up AeroFarms is shaking up the farming industry with its vertical farming method. Not only do its aeroponic farms use 95% less water than a traditional farm, they produce 130% higher yields of crops per square foot. The company raised $100 million (£79m) via a funding round in July 2019, while the vertical farming industry as a whole is expected to be worth $20 billion (£15.9bn) by 2026. 

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The Seatfrog app allows UK rail passengers to get round soaring ticket prices by bidding for first-class tickets for just $12 (£10). It currently works with the Avanti West Coast, CrossCountry, GWR and London North Eastern Railway rail companies and hopes to add more partners to its service soon. Recently, Seatfrog was one of 25 UK companies which were awarded £9.4 million ($11.8m) by the UK's Department for Transport in partnership with Innovate UK, in a drive to make rail travel easier, safer, more sustainable and more efficient. Could it be a challenger to other third-party train booking sites and apps? 

Push Doctor is a UK-based online medical consultation service that offers patients video consultations with a trained doctor via a smartphone, tablet or laptop. Users can also ask for prescriptions, referral letters and sick notes to be sent to their own email address or a local pharmacy. According to the Digital Healthcare Council, use of digital primary care services has skyrocketed since the start of the pandemic and Push Doctor has expanded to reach more than 200,000 more UK patients.

Meals kits such as those offered by Blue Apron and HelloFresh are stirring things up for the food production industry, and the meal kit industry is worth more than $5 billion (£4bn) globally. The demand for a quick and easy evening meal used to be met by processed food manufacturers. During the pandemic, British meal kit company Gousto has benefitted from high demand as people have cooked more at home and the company has reported a 28% increase in family boxes. It's even secured £33 million ($41.5m) extra funding during lockdown. 

As more and more people embrace vegan, vegetarian and flexetarian diets, companies such as LA-based Beyond Meat are making huge waves in the vegan food industry, which is expected to be worth $24.3 billion (£19.3bn) by 2026. The company claims its lab-grown meat alternatives have a smaller carbon footprint, are better for our health and use fewer resources than traditional meat products. Beyond Meat is currently valued at $8.8 billion (£7bn) and its shares rose over 77% in the first half of the year, according to S&P Global Intelligence. 

Another disruptor in the plant-based meat industry is Impossible Foods, whose realistically meaty-tasting Impossible Burgers were so popular last year that it struggled to meet demand. The company has raised $800 million (£635m) in venture investment and in January it launched a new pork alternative product. The company's valued at around $4.8 billion (£3.8bn), according to Reuters. 

Mobile-based banking app Revolut enables users to transfer money overseas in 29 currencies, withdraw cash abroad from ATMs with no or minimal fees, and access features relating to budgeting and cryptocurrencies, among others. The UK bank currently has more than six million customers and, along with other digital banks such as Monese and Monzo, is drawing younger customers away from traditional institutions. It was valued at $5.5 billion (£4.4bn) at its latest round of funding in February.

Founded in 2012, online estate agent Purplebricks was established in the UK but now also helps people buy and sell properties in parts of Canada and the US. The company essentially cuts out the middleman. Sellers visit the website, enlist a real estate agent for a flat fee, and see their home listed for sale in under an hour, giving them far greater control of the process. It hasn't all been easy going though, as the company has seen its share price plummet and one of its biggest investors, Andreas Wiele of German media company Axel Springer, step down this June.

Fleet management solution KeepTruckin aims to improve the life of the truck driver by bringing the industry into the digital age. In addition to electronic logs and fleet management tools, its platform includes GPS tracking and driver performance monitoring for fleet managers. In April last year, the San Francisco-based company raised $149 million (£123m) in order to double its headcount to 2,000 employees and was valued at $1.4 billion (£1.1bn). KeepTruckin recently partnered with digital freight company Convoy to share location data and improve efficiency. 

Described as the "Spotify of Magazines" by the Financial Times, digital magazine subscription service Readly gives subscribers "all you can read" access to thousands of magazines from a range of publishers worldwide for a basic monthly subscription. The Sweden-based company is available in more than 50 markets globally. In 2018, Readly saw total revenue grow by 54% to $21 million (£17m) from $13 million (£11m) the year before, and published more than 23,700 editions on its platform. The app has been especially popular during the COVID-19 pandemic with demand for its Gardening, Comics, Home & Renovation and Kids categories up significantly in March. Whether it will boost the magazine industry or accelerate its demise is open to question.

Now read about the education revolution driven by coronavirus

India-based investment app Groww was founded just three years ago but is already attracting a new generation of investors. Investing was once seen as the preserve of older generations but many younger people now believe that traditional banks won't give them the same kind of returns. That's where online applications such as Groww, which enables people to invest in mutual funds in a bid to democratise investing, step in. In June it raised $21.4 million (£17m) of Series B funding. 

The global diamond jewellery industry, worth $76 billion (£60.2bn) in 2018 according to Statista, has long been rife with corruption, from slave labour scandals to environmental destruction. Newcomer company Diamond Foundry, set up in 2010, is looking to shake things up. The firm is pioneering lab-grown diamonds which look just like the real deal, but are far more environmentally friendly and socially responsible. The company has raised $100 million (£79m) in funding.

Cabin is a luxury coach service that offers a dreamy, not to mention cost-effective, way to travel between Los Angeles and San Francisco. From just $119 (£95), travellers can book a luxury private sleeping cabin on an overnight coach rather than fly between the two Californian cities. Unlike on many budget airlines, passengers are entitled to take two items of luggage, plus there's free WiFi and a night-time tea. They are also spared the journey through airport security and get dropped off in the heart of the city. However, as demand for public transport has been greatly reduced due to the pandemic, start-ups such as Cabin face a rocky ride in the immediate future.

 

UK-based Globechain helps companies reduce waste by providing a marketplace for listing unwanted items, with a particular focus on the retail, commercial, hospitality, medical and construction industries. Founded in 2013, when terms such as the "circular economy" were less common, the company has already diverted more than 5.1 million kilos of equipment and other waste from landfill, reducing costs for companies and benefiting 14,000 communities in the UK and further afield.

PensionBee is disrupting the UK retirement savings industry by enabling users to manage their pensions via their mobile phone. Pensions are often considered complicated and boring, with many people having multiple pension pots from previous employers. The app aims to demystify pensions and help people stay on top of them, with full transparency on fees and jargon-free communication. Founded in 2014, PensionBee has more than 300,000 customers and about $610 million (£500m) invested with it. 

Sweden-based Truecaller was founded in 2009 by two students who wanted to create a service that would identify incoming calls from unknown numbers and now has more than 200 million daily users. Today it also offers a diverse range of communication services including video calling, payment services and instant chat. With offices in Stockholm and several Indian cities, Truecaller is also the most used communication app in India after apps such as Facebook Messenger and WhatsApp. However, the app was recently named as one of 89 apps banned by the Indian Army over concerns about information leaks. 

Festicket makes partying at festivals that little bit easier and more cost effective by packaging together tickets, travel, accommodation and other add-ons. Covering more than 1,000 festivals and working with more than 8,000 suppliers worldwide, Festicket has booked packages for more than 800,000 travellers since its launch in 2012. It also recently signed a deal with Californian festival Coachella to become its exclusive UK and Europe ticketing partner for 2020, and while this year's event was initially postponed and has now been cancelled, the US festival is still working with Festicket for 2021.

Now discover the colossal cost of canceling 2020's events

Founded with the aim of making bus travel both comfortable and affordable, Flixbus is a combination of a tech start-up, transportation company and e-commerce platform. Launched in Germany in 2013, Uber-like FlixBus now offers domestic and cross-border services in Europe and the US, standing as a competitor to established coach companies such as Megabus and Greyhound by offering dynamic pricing based on demand. Last year, it raised €500 million ($550m/£453m) in what was Germany's biggest funding round to date, putting a valuation on the firm of more than €2 billion ($2.2bn/£1.8bn). On 2 July this year the service launched in the UK and it will partner with local bus companies to provide its services. 

Canva is an online design tool that lets non-designers and professionals alike create social media graphics, presentations and other documents using their smartphone or tablet. The Sydney-based start-up offers users a range of stock fonts, photos and illustrations to create their own works, giving traditional, expensive agencies a run for their money. Canva was recently named one of the world's top 'unicorn' companies by CNBC, with a valuation of $6 billion (£4.8bn).

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