Sapphire is the first confidential EVM-compatible Network. This means that it is the only network where developers can build Smart Contracts in Solidity which can hide aspects of state. This can added flexibility for developers will lead to many numerous performance benefits and improvements in the user experience when interacting with these dapps. Use cases can be seen in a variety of sectors like DeFi, Gaming, NFTs, Decentralized Identity, and Social applications. Just as web2 was empowered by privacy protocols like HTTPS, we believe web3 will be propelled forward from these new functionalities.
The advantage to Sapphire over some Emerald, or Cipher, depends on what type of enviroment and features the developer is looking for. For solidity devs looking to incorporate confidentiality feature, Sapphire is the ideal ParaTime. I hope this helps!