Imagine an application that doesn’t run on one server but harnesses the excess power of thousands of computers globally and that can be controlled by business automation software that ensures if a specific parameter is met, only then can a function be carried out.

That’s a distributed application – or dApp, as it's sometimes abbreviated – and there are thousands available for download.

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Running atop a blockchain, peer-to-peer (P2P) network that acts as a kind of operating system, dApps create an innovative open-source software ecosystem that is both secure and resilient. And it allows developers to create new online tools, many of which have piqued the interest of global business markets.

"DApps will pool resources across numerous machines globally," said Juniper senior analyst Lauren Foye. "The results are applications which do not belong to a sole entity, [but] rather are community-driven."

Bitcoin was arguably the first dApp, enabling anyone in the world to download a bit of open-source code to join a blockchain network and verify transactions using a “mining” algorithm, thereby generating digital currency (cryptocurrency) as a reward.

Like a RAIDed storage array, if one of the computers (or nodes) running the dApp software goes down, another node instantaneously resumes the task.

Because smart contracts, or self-executing business automation software, can interact with dApps, they're able to remove administrative overhead, making them one of most attractive features associated with blockchain. While blockchain acts as an immutable electronic ledger, confirming that transactions have taken place, smart contracts execute predetermined conditions; think about a smart contract as a computer executing on "if/then," or conditional, programming.

“DApps interact with smart contracts that are on the blockchain. So dApps support the user interface into the back-end smart contract that writes data to the blockchain,” said Avivah Litan, a vice president of research at Gartner.

DApps run the gamut, from digital asset exchanges like LBank to online gambling like PokerKing and games like Cryptokitties. (LBank holds the equivalent of more than $1.4 billion in cryptocurrency.)

Depending on the blockchain platform (there are more than a dozen and vastly more modifications of those), dApps are also used by small and large businesses to track and trace goods as they move around the globe and enable cross-border financial transactions without the need of a middleman such as a central bank or clearing house.

The following is a list of 10 game-changing dApps – both business and consumer – in no particular order, according to industry experts such as Litan, and the Linux Foundation’s Hyperledger organization. Some were chosen because of popularity, others because they’re innovative and feature-rich.

This secure middleware is promoting an open standard for a secure, decentralized data input or “oracle” system that validates information from external feeds. In short, Chainlink offers any smart contract secure access to data feeds, APIs and payments.

It’s so promising that Google is testing it as the intermediary for its BigQuery platform-as-a-service data warehouse.

In blockchain, an oracle can be a database or other data source that feeds traditional business information to a smart contract running on a blockchain ledger. Chainlink basically secures the data feed to and from the smart contracts and makes it that much harder to compromise, since it relies on the same types of consensus mechanisms blockchains use to come to agreement on the validity of a transaction.

A smart contract requires multiple inputs to prove contractual performance and Chainlink, which can connect to any API, can be used to validate money transfers from a bank or any number of other industry financial players, such as Visa or PayPal. Oraces are needed because smart contracts don’t interface with external systems or information directly; the oracle allows a smart contract to interact with any external system outside the blockchain (or DLT) they run on, according to Gartner.

“This function is critical, especially in permissioned blockchain use cases, so that smart contracts can automatically and reliably respond to changing external circumstances, events and information. Some common examples in financial services include being notified of changing interest rates or asset prices,” Gartner said.

A web browser with almost 9 million active users, Brave is attempting to turn the online advertising model upside down by putting consumers in the driver's seat. The app creates a new measure of value in the advertising world where “consumer attention” is used to set value more than unverifiable views or clicks on a webpage, Gartner said in its Cool Vendors in Blockchain Applications report.

Co-founded by Brendan Eich, inventor of JavaScript and a founder of Mozilla and Firefox, Brave seeks to create a blockchain-based digital advertising and services platform that gives both information control and privacy back to users – an increasingly hot topic after the rollout of GDPR. The dApp enables key participants in the ad ecosystem (namely advertisers, publishers and browser users) to participate in a new business model that cuts out excess intermediation between publishers and advertisers by rewarding users with “Basic Attention Tokens (BATs) or Brave Rewards that can be traded like bitcoin.

“If successful, it will greatly reduce the power and influence of the powerful Internet gatekeepers, e.g. Google and Facebook,” Litan wrote via email.

In this mix, we had to include at least one game. EOS Dynasty, which has nearly 12,000 unique daily users, claims to be the first role-playing, player-versus-player (PvP) game based on blockchain.

Players create up to three “heroes” or warriors who can fight battles to gain experience and grow in power and capabilities by collecting materials, forging equipment and riding mounts (horses, tigers, tortoises, etc.). The player can also be awarded Three Kingdoms Tokens (TKTs), a limited cryptocurrency (ahem, limited to 1 billion), that enables users to earn material or profit dividends in two marketplaces based on a smart contract.

Tokens are collected through a variety of accomplishments, including trading, battlefield conflicts, tasks and PvP fights. Dividends from the game are only awarded after players reach specific military ranks, enabling them to stake TKT cryptocurrency coins and then earn from them.

A decentralized credit service that runs on the Ethereum blockchain platform, MakerDAO supports Dai, a stablecoin whose value is pegged to the U.S. dollar.

Anyone can use MakerDAO to open a Collateralized Debt Position (CDP), lock in ETH (Ethereum cryptocurrency) as collateral, and generate Dai as debt against that collateral, according to Marta Piekarska-Geater, director of Ecosystem at Hyperledger.

Users can borrow Dai up to 66% of their collateral’s value (150% collateralization ratio).

“CDPs that fall below that rate are subject to a 13% penalty and liquidation (by anyone) to bring the CDP out of default. Liquidated collateral is sold on an open market at a 3% discount,” Piekarska-Geater said via email.

This dApp and consultancy is striving to solve problems with Supplier Information Management systems, which today are slow, inefficient and unable to adapt to new requirements quickly. Chainyard, a permissioned blockchain-based network, is designed to improve supplier validation, onboarding and life cycle information management.

In many cases, supplier information management systems still leverage dated technology and processes; email, spreadsheets and word documents are still used to verify identities and track documents like ISO certifications, bank account info, tax certifications, and certificates of insurance throughout the lifecycle of a supplier.

In partnership with IBM, Chainyard launched Trust Your Supplier, a blockchain-based service giving buyers access to their supplier’s verified background information for the purpose of onboarding them onto a supply chain. The ultimate goal: frictionless connectivity across supply chains.

When it comes to charitabe giving, the “donation sector suffers from lack of transparency and traceability,” Piekarska-Geater said. That's where TRACEDonate comes in: its identity management platform is designed to allow for transparent and traceable cross-border remittances and giving.

The dApp created by AID:Tech connects charitable organizations and donors to beneficiaries. It hopes to give donors peace of mind that their funds will be used for the intended purposes by those in need, whether it’s for buying groceries or utilities, rather than alcohol, etc., according to Piekarska-Geater.

“It is nearly impossible for regular donors to gain transparency around the distribution of charity and what effect it is having on improving lives,” Piekarska-Geater said. “Unfortunately, this lack of trust affects end-beneficiaries the most, who are also most in need of support.”

Blockchain is used to prove the identity of the charitable organization and/or the individual to which a donation is made. It then allows the donor to track how the money is spent, because the funds are kept in a digital online wallet. Donors can also specify how they want the money used, whether for medical aid, food or other emergency supplies.

Like similar dApps that emerged before it, Circulor is a dApp offering supply chain traceability – in this case for the electric vehicle and electronics industries. It provides traceability to demonstrate the ethical and sustainable sourcing of raw materials used in the production of the latter.

The track-and-trace platform enables users to secure deliveries, manage payments and check provenance of raw materials, and provides a host of other features, making Circulor designed for real-world complexity.

Created by Avanza Innovations, Cipher is middleware that supports a portfolio of four blockchain dApps for government agencies and regulators in different regions; it includes a reconciliation and settlement network, tokenization of loyalty points, a procurement payment network and a document-exchange, verification and compliance network for banks and their customers.

The focus areas for Cipher's blockchain-based solutions are Digital Government Transformation and Financial Regulation & Supervision. The company works with entities in Dubai, including Smart Dubai Government, the Department of Finance, the Dubai Electric & Water Authority, the Knowledge & Human Development Authority, Emirates NBD Bank and Network International.

“The dApp reduced 40 days of manual reconciliation to instant reconciliation, thereby cutting huge wastage in Dubai’s government functions,” Piekarska-Geater said.

This app is used by businesses to verify customer identities and streamline the on-boarding process in a way that meets know-your-customer (KYC) regulations. It can verify individuals as well as corporate and institutional business clients for criminal or prohibited activities in real-time through a partner sanctions and watchlists database that spans more than 240 countries.

Together with a self-sovereign identity dApp from partner company SelfKey, KYC-Chain lets users store their own certified identity details on-chain and control public access to their credentials by offering up public keys when access is needed. The dApp allows users to pay individually for 10 services, such as accredited investor checks, crypto funds screening, ID verification and document authentication. The service also lets users check client crypto wallet spending to check against known-risk indicators and comply with anti-money laundering rules.

Built on the Hyperledger Fabric business platform, DLT.sg (Distributed ledger Technologies, Singapore) includes a series of enterprise-grade blockchain dApp modules focused on supply chain and counterfeit recognition technologies; DLT.sg is built for collaborative ecommerce in large supply-chain organizations. It enables trade finance, tracks end-to-end product flow and delivers a model for unlocking inventory and freeing up cash.

For example, SKR,sg’s SmartCode for Pharma is focused on resolving Pharma counterfeits by tracing their provenance throughout the production process. Another module, SmartFIN, is a dApp to help fund trade between multinational corporations, commodity traders and banks; it creates a permissioned online ledger through which corporations can securely interact with their financial institutions in the negotiation of trade finance, bonding & guarantees and risk mitigation.

DLT.sg’s dApps can also integrate with SAP and Microsoft software via APIs, if needed, in order to connect to legacy data sources.