Is Loopring on Ethereum?

Could you elaborate on the current status of Loopring and its relationship with Ethereum? Specifically, is Loopring built on the Ethereum blockchain? If so, what are the key benefits and considerations for utilizing Loopring on Ethereum? How does this integration enhance the functionality and scalability of Loopring's services? Additionally, are there any plans for Loopring to expand to other blockchains or has it chosen Ethereum as its primary platform due to specific advantages? Understanding the underlying technology and strategic choices behind this partnership is crucial for investors and developers alike.