"I have iterate above json data by below code"

The code you posted pulls in 10 modules, yet none of the code posted makes any use of them. You can't have run the code you posted as perl would have pointed out your mistake, which is visible if you look at the few lines. Again How do I post a question effectively?.

If you want to iterate through the key/value pairs of the "appLinks" hash, here's an example. Note that the OPed JSON string must be fixed before it can be decoded (misplaced commas), and also that I've added some more pairs for the example.

Win8 Strawberry 5.8.9.5 (32)  Mon 09/13/2021  6:17:03
C:\@Work\Perl\monks
>perl -Mstrict -Mwarnings

use JSON;
use Data::Dump qw(dd);

# fixed and enhanced JSON string.
my $json_string = '
[
{
            "visio": {
            "Launch": false,
            "hide": {
                "iOS": true
                         },
            "appLinks": {
                "preview_sandbox_1_link": true,
                "fooble": false,
                "wibble": 42,
                "blarfl": "darble"
            }
        }

        }
    ]
';
# print "$json_string \n";  # for debug

my $arrayref = decode_json $json_string;
# dd $arrayref;  # for debug

# convenience variable.
my $appLinks_hashref = $arrayref->[0]{'visio'}{'appLinks'};

for my $appLink_key (keys %{ $appLinks_hashref }) {
    print "appLink key '$appLink_key' -> ";
    print "appLink value '$appLinks_hashref->{$appLink_key}' \n";
    }

^Z
appLink key 'wibble' -> appLink value '42'
appLink key 'blarfl' -> appLink value 'darble'
appLink key 'preview_sandbox_1_link' -> appLink value 'true'
appLink key 'fooble' -> appLink value 'false'
[download]

it's because even after three years here you don't know basic Perl or how to post a question.

.oO{ troll? }