When you install a 3rd party application in LinkedIn, it is most likely that it will request access to some of basic profile and contacts information, which may include photos, names, phone numbers, connections, email addresses and other personal details.
Restrict Access to your Personal Data in LinkedIn
Connect to your LinkedIn account. Click on Account & Settings
> Privacy & Settings
Go to Groups, Companies & Applications
and click on Turn on/off data sharing with 3rd party applications
Clear the Yes, share my data (including basic profile and contact information) with third party applications
checkbox and click on Save Changes