Logmein is like TeamViewer or Parallels Access. It is an app used for remote access to your computer from another device. What I mean by that is I can work from my iPhone on my iMac even if I am hundreds of miles away. I would not install it if someone that you do not know has asked you too! There are a lot of scams where they will phone you and tell you they can see problems on your computer and ask you to install. they can then access your computer and steal your information.
Please sign up and become a member if you have any further questions in regards to it.