Blockchain technology was first used for financial transactions. But nowadays, its scope is increasing and applies in a variety of industries like e-commerce, data management, energy, gaming, e-governance, and many more. There are several commercial and open-source platforms available to provide the framework for creating applications that support a blockchain. Hyperledger and Ethereum are actively improving the blockchain ecosystem by creating advanced cross-industry blockchain technologies.

Hyperledger is an open-source collaboration that provides tools and techniques for developing an enterprise-grade blockchain solution. While Ethereum is an open-source and leading platform designed for developers, organizations, and business to build and deploy blockchain applications.

Several platforms were actively involved in developing blockchain applications. However, the blockchain space is dynamic, and new platforms may have emerged or gained prominence since then. Here are some notable platforms that were actively involved in blockchain development around that time:

Ethereum: Widely known for smart contract functionality, Ethereum is a decentralized platform that enables the creation of decentralized applications (DApps).
Binance Smart Chain (BSC): Developed by the cryptocurrency exchange Binance, BSC is a blockchain platform that supports smart contracts and decentralized applications.
Cardano: Focused on scalability, sustainability, and interoperability, Cardano is a blockchain platform known for its research-driven approach.
Polkadot: Created by Ethereum co-founder Dr. Gavin Wood, Polkadot is a multi-chain platform designed for interoperability between blockchains.
Tezos: A self-amending blockchain that allows stakeholders to directly participate in the decision-making process for protocol upgrades.
Solana: Known for its high throughput and low transaction costs, Solana is a blockchain platform designed for decentralized applications and crypto projects.
Avalanche: A platform for launching custom blockchain networks and interoperable dApps.
NEO: Often referred to as “Ethereum of China,” NEO supports smart contracts and aims to digitize assets using blockchain technology.
Cosmos: Focuses on interoperability between different blockchains, allowing them to communicate and transfer assets seamlessly.
Hyperledger: A project under the Linux Foundation, Hyperledger hosts several blockchain frameworks and tools for enterprise blockchain development.

Keep in mind that the blockchain landscape evolves rapidly, and new platforms may have emerged or gained prominence since my last update. It’s recommended to check the latest developments and updates in the blockchain space for the most current information.