Grammar : On time and in time

What is the difference between on time and in time? 

"On time" = at the planned time; neither late nor early.
e.g. Peter wants the meeting to start exactly on time. 

"In time" = with enough time to spare; before the last moment.
e.g. He would have died if they hadn’t got him to the hospital in time.


What is the difference between in the end and at the end? 

"In the end" = finally, after a long time.  
e.g. In the end, I got a visa for Russia. 

"At the end" = at the point where something stops.
e.g. I think the film’s a bit weak at the end. 

Here's you can find the same stuff but it's in Russian :) In time/On time In the end/ At the end