How to implement displaying data received from three different sources or queries simultaneously in an interface or application?

To display data from three different sources simultaneously in an iOS app, a common approach is to use asynchronous result aggregation. For example, you can use DispatchGroup to track the completion of all three requests, and then update the interface:

let group = DispatchGroup()
var data1: DataType1?
var data2: DataType2?
var data3: DataType3?

group.enter()
fetchDataFromSource1 { result in
    data1 = result
    group.leave()
}

group.enter()
fetchDataFromSource2 { result in
    data2 = result
    group.leave()
}

group.enter()
fetchDataFromSource3 { result in
    data3 = result
    group.leave()
}

group.notify(queue: .main) {
    // All data received, update UI
    updateUI(data1: data1, data2: data2, data3: data3)
}

You can also use Combine or async/await (in newer versions of Swift) for more convenient handling of multiple asynchronous data streams and their aggregation.