Is simplified payment validation (SPV) decentralized?
Viz., when an SPV client wants to verify a payment, does it connect to a central server or to several random peers, checking that their Merkle tree traversals for the transaction to be verified all agree?
"Choose your Bitcoin wallet" from Bitcoin.org says (e.g., for GreenAddress's Android wallet) "Decentralized validation," which it describes as:
This wallet connects to a random server from a list. This means some trust in third parties is required when verifying payments. However, it is not as secure as a full node like Bitcoin Core.
How is "connect[ing] to a random server from a list" decentralized?
However (e.g., for iOS's BreadWallet) it says "Simplified validation" instead, which it describes as:
This wallet uses SPV and the Bitcoin network. This means very little trust in third parties is required when verifying payments. However, it is not as secure as a full node like Bitcoin Core.