Cydia only works with a Jailbreak.
Currently there isn't a jailbreak for 10.3.3, latest is for 10.1.1 or 10.2
So pretty much, you can't get cydia.
Phone: iPhone 6
Version: 10.3.3
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YouTube "How To Install Cydia.." FAKE ALL :l
PLEASE HELP ME..
Cydia only works with a Jailbreak.
Currently there isn't a jailbreak for 10.3.3, latest is for 10.1.1 or 10.2
So pretty much, you can't get cydia.
Like Harry said, I dont think its possible at the moment