Sorting an array of arrays in swift 3

I would suggest you create a struct or class to package this related data together:

struct Person {
    let id: Int
    let picture: String // This should probably be a URL, NSImage or UIImage
    let firstName: String
    let lastName: String
}

And then define your instances with the correct types (e.g. the id is an Int, not a String representation of an Int.

let people = [
    Person(
        id: 1,
        picture: "picture1.png",
        firstName: "John",
        lastName: "Smith"
    ),
    Person(
        id: 2,
        picture: "picture2.png",
        firstName: "Mike",
        lastName: "Rutherford"
    ),
]

From there, you can sort it any which way you please:

people.sorted{ $0.id < $1.id }
people.sorted{ $0.id > $1.id }
people.sorted{ $0.picture < $1.picture }
people.sorted{ $0.picture > $1.picture }
people.sorted{ $0.firstName < $1.firstName }
people.sorted{ $0.firstName > $1.firstName }
people.sorted{ $0.lastName < $1.lastName }
people.sorted{ $0.lastName > $1.lastName }

Notice, that index ranged is not checked, what could lead to a fatal error at runtime. Check Alexanders comment! :)

var myArray: [[String]] =
[
    ["1", "picture1.png", "John", "Smith"],
    ["2", "picture2.png", "Mike", "Rutherford"],
]

func sort<T: Comparable>(ArrayOfArrays: [[T]], sortingIndex: Int, sortFunc: (T, T) -> Bool)) -> [[T]] {
    return ArrayOfArrays.sorted {sortFunc($0[sortingIndex], $1[sortingIndex])}
    }
}

print(sort(ArrayOfArrays: myArray, sortingIndex: 0, sortFunc: <)) 
//[["1", "picture1.png", "John", "Smith"], ["2", "picture2.png", "Mike", "Rutherford"]]
print(sort(ArrayOfArrays: myArray, sortingIndex: 0, sortFunc: >)) 
//[["2", "picture2.png", "Mike", "Rutherford"], ["1", "picture1.png", "John", "Smith"]]

Swift's Array has a built-in sort function. Just call it.

myArray[0].sort { $0.compare($1, options: .numeric) == .orderedAscending }
myArray[1].sort { $0.compare($1, options: .numeric) == .orderedDescending }

To sort the arrays using numeric string comparison (e.g. where "2" < "10") of the item at a particular index:

let index = 1  // sort by second entry
myArray.sort { $0[index].compare($1[index], options: .numeric) == .orderedAscending }

If you don't need numeric comparisons (e.g. where "10" < "2"):

myArray.sort { $0[index] < $1[index] }

As others point out, though, you really should be using arrays of custom struct or class rather than representing your objects as mere array of strings.