1 People can see your Instagram photos
When you link Instagram to Tinder, the people you didn't match can still see your Instagram photos. A person can easily click on your profile and see all of your Instagram photos before matching you.
2 The most recent 34 pictures will appear
Your 34 most recent Instagram pictures will appear in your account. People will be able to visit your Instagram account to see more pictures.
3 Pictures will appear even if your account is private
Your most recent Instagram pictures will appear on Tinder even if your account is private. If your account is private, a person will only see your most recent pictures, but if they visit your Instagram account through the link, they won't see anything.
4 People can visit your Instagram profile
When you link Instagram to Tinder, any person can easily visit your Instagram profile. Tinder will provide a link to your Instagram account and so the people who haven't matched you yet can still visit your profile on Instagram. (See Why is Instagram so FAKE?)
5 People can track your social network accounts
Once a person manages to access your real Instagram account, they can use the information they find there to track your other social network accounts.
6 People will get your Instagram information
When you connect both accounts, people will be able to get your full name and your personal life from your Instagram profile. People will also find your Instagram username. (See Why is Tinder bad for your mental health?)
7 Your Instagram's privacy settings won't change
Linking both accounts won't change your Instagram's privacy settings in any way. People will only be able to see your recent pictures through your Tinder account but they won't be able to do it on Instagram if your account is private.