Fintech start-ups gained massive popularity in 2015, showing signs of significant potential for growth and nearly endless opportunities for innovation. In fact, recent Fintech reviews have shown that these online companies have the potential to take away as much as $4.7 worth of revenue from traditional financial services.

Currently, Fintech companies have penetrated account management, lending and financing, payment processing, financial assets and capital markets. Undoubtedly, their major basis of appeal is their focus on their customer’s needs. Fintech companies provide the means and the technology for businesses to handle digital transactions quickly, safely and cost-effectively, when compared with traditional financial services.

Whether you are just getting into Fintech or have been interested in the technology for quite some time now, here are some currently trending Fintech start-ups to look out for.

Adyen

Adyen is a fast growing, international payments processing company with Uber, Spotify and Facebook among its prominent clients. The Dutch firm was created in 2006 and offers payment services for a variety of platforms.

Adyen has expanded and flourished due to targeted sponsorship over the years. Only last year, the company raised a respectable but undisclosed sum of money from a wealth management fund called Iconiq, which includes Mark Zuckerberg among its clients.

Currency Cloud

Established in early 2012, Currency Cloud is a London-based Fintech company operating in the payments sector. The company offers a cloud-based platform that allows users to send and receive money worldwide through an application programming interface. Compared with banks, Currency Cloud completes transactions more cheaply and faster.

Currency Cloud now processes at least $15 billion a year and has over 125 customers all over the world. This Fintech start-up raised $18 million last year from Sapphire Ventures and Japanese e-commerce giant Rakuten.

Klarna

Klarna is a Swedish payment-processing start-up, which is similar to PayPal.  Simplifying payments is the main mission of this application. Klarna doesn’t require registration and orders are easy to place by simply entering your email and zip code. According to Fintech reviews, last year Klarna raised $2.25 billion from venture capital firm Northzone and Wellington Management, while the Wellcome Trust bought 80 million dollars worth of its stock.