i have a very play full great dane who loves to run of to any other dog that he can see the only problem is he wont come back when i call him.other dog owners get very scared when they see him as he is a very big dog even though he would never hurt anyone or another dog he just wonts to run and play.i have tried all sorts of stuff but its no good i dont want to keep him on a lead as all he wants to do is play.he is 13 months old and soft as a giant.

Have you ever taught him to come back when called?  Dogs don't know their names automatically, like everything else, they have to be taught.....

I'm afraid with a a dog the size of a GD most owners are going to be worried if it comes running towards their dog totally ignoring its owner.
You should know that by having your dog off lead and not doing as its told technically you are breaking the law since it states that a dog must be under control at all times.
You should also bare in mind that if your dog runs up to another dog who is on lead because it is aggressive and a fight ensues YOU are at fault...not the owner of the aggressive dog.
I would suggest you find a good local training class and go along ...teach your boy how to behave properly and then everyone will be safe and happy
Archer

Hear Hear Archer!