@TuHuynh : Firstly, Yes ideviceinstaller is on my mac and when I try to do this : find / -name ideviceinstaller
I got this on my Terminal :
find: /.DocumentRevisions-V100: Permission denied
find: /.fseventsd: Permission denied
find: /.Spotlight-V100: Permission denied
find: /.Trashes: Permission denied
find: /dev/fd/EB_QA_AUTO: No such file or directory
find: /dev/fd/EB_QA_AUTO: No such file or directory
find: /Library/Application Support/Apple/ParentalControls/Users: Permission denied
find: /Library/Application Support/ApplePushService: Permission denied
find: /Library/Application Support/com.apple.TCC: Permission denied
find: /Library/Caches/com.apple.iconservices.store: Permission denied
find: /Library/SystemMigration/History/Migration-BC66D93B-3F47-4F5B-8406-5972A1CB6401/QuarantineRoot/System/Library/DirectoryServices/DefaultLocalDB/Default: Permission denied
find: /private/etc/cups/certs: Permission denied
find: /private/tmp/com.apple.launchd.JpJyIw3sOx: Permission denied
find: /private/tmp/com.apple.launchd.PSldkfn5l9: Permission denied
find: /private/var/agentx: Permission denied
find: /private/var/at/tabs: Permission denied
find: /private/var/at/tmp: Permission denied
find: /private/var/audit: Permission denied
find: /private/var/backups: Permission denied
find: /private/var/db/applepay: Permission denied
find: /private/var/db/caches/opendirectory: Permission denied
find: /private/var/db/ConfigurationProfiles/Setup: Permission denied
find: /private/var/db/datadetectors: Permission denied
find: /private/var/db/dhcpclient: Permission denied
find: /private/var/db/diagnostics: Permission denied
find: /private/var/db/dslocal/nodes/Default: Permission denied
find: /private/var/db/geod: Permission denied
find: /private/var/db/launchd.db/com.apple.launchd.peruser.0: Permission denied
find: /private/var/db/launchd.db/com.apple.launchd.peruser.200: Permission denied
find: /private/var/db/launchd.db/com.apple.launchd.peruser.201: Permission denied
find: /private/var/db/launchd.db/com.apple.launchd.peruser.202: Permission denied
find: /private/var/db/launchd.db/com.apple.launchd.peruser.212: Permission denied
find: /private/var/db/launchd.db/com.apple.launchd.peruser.55: Permission denied
find: /private/var/db/launchd.db/com.apple.launchd.peruser.88: Permission denied
find: /private/var/db/launchd.db/com.apple.launchd.peruser.89: Permission denied
find: /private/var/db/launchd.db/com.apple.launchd.peruser.92: Permission denied
find: /private/var/db/launchd.db/com.apple.launchd.peruser.97: Permission denied
find: /private/var/db/locationd: Permission denied
find: /private/var/db/lockdown: Permission denied
find: /private/var/db/nsurlsessiond: Permission denied
find: /private/var/db/securityagent: Permission denied
find: /private/var/db/Spotlight: Permission denied
find: /private/var/db/sudo: Permission denied
find: /private/var/db/TokenCache: Permission denied
find: /private/var/folders/zz/zyxvpxvq6csfxvn_n0000000000000/0/com.apple.pluginkit: Permission denied
find: /private/var/folders/zz/zyxvpxvq6csfxvn_n0000000000000/0/com.apple.revisiond/com.apple.revisiond.temp: Permission denied
find: /private/var/folders/zz/zyxvpxvq6csfxvn_n0000000000000/0/com.apple.revisiond.temp: Permission denied
find: /private/var/folders/zz/zyxvpxvq6csfxvn_n0000000000000/0/com.apple.Spotlight: Permission denied
find: /private/var/folders/zz/zyxvpxvq6csfxvn_n0000000000000/C: Permission denied
find: /private/var/folders/zz/zyxvpxvq6csfxvn_n0000000000000/T: Permission denied
find: /private/var/folders/zz/zyxvpxvq6csfxvn_n000003000000r/T: Permission denied
find: /private/var/folders/zz/zyxvpxvq6csfxvn_n000006w00001q/C: Permission denied
find: /private/var/folders/zz/zyxvpxvq6csfxvn_n000006w00001q/T: Permission denied
find: /private/var/folders/zz/zyxvpxvq6csfxvn_n0000084000021/C: Permission denied
find: /private/var/folders/zz/zyxvpxvq6csfxvn_n0000084000021/T: Permission denied
find: /private/var/folders/zz/zyxvpxvq6csfxvn_n00000b400002s/C: Permission denied
find: /private/var/folders/zz/zyxvpxvq6csfxvn_n00000b400002s/T: Permission denied
find: /private/var/folders/zz/zyxvpxvq6csfxvn_n00000bh00002w/C: Permission denied
find: /private/var/folders/zz/zyxvpxvq6csfxvn_n00000bh00002w/T: Permission denied
find: /private/var/folders/zz/zyxvpxvq6csfxvn_n00000c4000031/C: Permission denied
find: /private/var/folders/zz/zyxvpxvq6csfxvn_n00000c4000031/T: Permission denied
find: /private/var/folders/zz/zyxvpxvq6csfxvn_n00000s0000068/C: Permission denied
find: /private/var/folders/zz/zyxvpxvq6csfxvn_n00000s0000068/T: Permission denied
find: /private/var/folders/zz/zyxvpxvq6csfxvn_n00000s4000069/C: Permission denied
find: /private/var/folders/zz/zyxvpxvq6csfxvn_n00000s4000069/T: Permission denied
find: /private/var/folders/zz/zyxvpxvq6csfxvn_n00000s800006_/C: Permission denied
find: /private/var/folders/zz/zyxvpxvq6csfxvn_n00000s800006_/T: Permission denied
find: /private/var/folders/zz/zyxvpxvq6csfxvn_n00000sm00006d/C: Permission denied
find: /private/var/folders/zz/zyxvpxvq6csfxvn_n00000sm00006d/T: Permission denied
find: /private/var/folders/zz/zyxvpxvq6csfxvn_n00000t800006k/T: Permission denied
find: /private/var/folders/zz/zyxvpxvq6csfxvn_n00000th00006m/C: Permission denied
find: /private/var/folders/zz/zyxvpxvq6csfxvn_n00000th00006m/T: Permission denied
find: /private/var/folders/zz/zyxvpxvq6csfxvn_n00000tm00006n/T: Permission denied
find: /private/var/folders/zz/zyxvpxvq6csfxvn_n00000vr00006y/C: Permission denied
find: /private/var/folders/zz/zyxvpxvq6csfxvn_n00000vr00006y/T: Permission denied
find: /private/var/folders/zz/zyxvpxvq6csfxvn_n00000xc00007b/C: Permission denied
find: /private/var/folders/zz/zyxvpxvq6csfxvn_n00000xc00007b/T: Permission denied
find: /private/var/folders/zz/zyxvpxvq6csfxvn_n00000y000007h/C: Permission denied
find: /private/var/folders/zz/zyxvpxvq6csfxvn_n00000y000007h/T: Permission denied
find: /private/var/folders/zz/zyxvpxvq6csfxvn_n00000y400007j/T: Permission denied
find: /private/var/folders/zz/zyxvpxvq6csfxvn_n00000y800007k/C: Permission denied
find: /private/var/folders/zz/zyxvpxvq6csfxvn_n00000y800007k/T: Permission denied
find: /private/var/folders/zz/zyxvpxvq6csfxvn_n00000yc00007l/T: Permission denied
find: /private/var/folders/zz/zyxvpxvq6csfxvn_n00000z000007r/0/com.apple.notificationcenter: Permission denied
find: /private/var/folders/zz/zyxvpxvq6csfxvn_n00000z000007r/0/com.apple.pluginkit: Permission denied
find: /private/var/folders/zz/zyxvpxvq6csfxvn_n00000z000007r/C: Permission denied
find: /private/var/folders/zz/zyxvpxvq6csfxvn_n00000z000007r/T: Permission denied
find: /private/var/folders/zz/zyxvpxvq6csfxvn_n0000104000081/C: Permission denied
find: /private/var/folders/zz/zyxvpxvq6csfxvn_n0000104000081/T: Permission denied
find: /private/var/folders/zz/zyxvpxvq6csfxvn_n000010c000083/C: Permission denied
find: /private/var/folders/zz/zyxvpxvq6csfxvn_n000010c000083/T: Permission denied
find: /private/var/folders/zz/zyxvpxvq6csfxvn_n000010m000085/C: Permission denied
find: /private/var/folders/zz/zyxvpxvq6csfxvn_n000010m000085/T: Permission denied
find: /private/var/folders/zz/zyxvpxvq6csfxvn_ngzzzzzvzzzzzy/C: Permission denied
find: /private/var/folders/zz/zyxvpxvq6csfxvn_ngzzzzzvzzzzzy/T: Permission denied
find: /private/var/jabberd: Permission denied
find: /private/var/lib/postfix: Permission denied
find: /private/var/log/com.apple.revisiond: Permission denied
find: /private/var/ma: Permission denied
find: /private/var/root: Permission denied
find: /private/var/run/com.apple.xpcproxy.RoleAccount.staging: Permission denied
find: /private/var/run/mds: Permission denied
find: /private/var/spool/cups: Permission denied
find: /private/var/spool/mqueue: Permission denied
find: /private/var/spool/postfix/active: Permission denied
find: /private/var/spool/postfix/bounce: Permission denied
find: /private/var/spool/postfix/corrupt: Permission denied
find: /private/var/spool/postfix/defer: Permission denied
find: /private/var/spool/postfix/deferred: Permission denied
find: /private/var/spool/postfix/flush: Permission denied
find: /private/var/spool/postfix/hold: Permission denied
find: /private/var/spool/postfix/incoming: Permission denied
find: /private/var/spool/postfix/maildrop: Permission denied
find: /private/var/spool/postfix/private: Permission denied
find: /private/var/spool/postfix/public: Permission denied
find: /private/var/spool/postfix/saved: Permission denied
find: /private/var/spool/postfix/trace: Permission denied
find: /System/Library/Caches/com.apple.coresymbolicationd: Permission denied
find: /System/Library/Caches/com.apple.receiptInstaller: Permission denied
find: /System/Library/DirectoryServices/DefaultLocalDB/Default: Permission denied
find: /System/Library/User Template: Permission denied
/Users/EB_QA_AUTO/.npm/appium/1.0.0/package/build/libimobiledevice-macosx/ideviceinstaller
find: /Users/Guest/Desktop: Permission denied
find: /Users/Guest/Documents: Permission denied
find: /Users/Guest/Downloads: Permission denied
find: /Users/Guest/Library: Permission denied
find: /Users/Guest/Movies: Permission denied
find: /Users/Guest/Music: Permission denied
find: /Users/Guest/Pictures: Permission denied
find: /Users/Guest/Public/Drop Box: Permission denied
/usr/local/bin/ideviceinstaller
/usr/local/Cellar/ideviceinstaller
/usr/local/Cellar/ideviceinstaller/1.1.0_2/bin/ideviceinstaller
/usr/local/lib/node_modules/appium/build/libimobiledevice-macosx/ideviceinstaller
/usr/local/opt/ideviceinstaller
/usr/local/var/homebrew/linked/ideviceinstaller
find: /usr/sbin/authserver: Permission denied
Also, I tried your Error: Could not initialize ideviceinstaller; make sure it is installed and works on your system but this dint work for me 
Please help.!!