If your client supports it, it can subscribe to events sent by the server when a new block is received or when new transactions that affect a given account are detected in the mempool.

subscription {
  events(idAccount: 1) {
    type
    txid
    height
  }
}

Subscribe to events for account 1. Events are either:

• new block for which height is set,
• new transaction for which the txid is set
• type indicates the type of the event BLOCK or TX