One Strap Backpacks
If you have ever taken your regular two strap backpack and put both straps on one shoulder than you know how awkward that can be. It is nice if you like to wear it both ways (sometimes with two straps over both shoulders) but if you find yourself consistently wearing your backpack on one shoulder you are going to find a one strap backpack is the best choice for comfort as well as reliability.
Wearing a one strap backpack designed to be worn that way is going to secure your bag a lot better because the strap and weight balance is usually fit to the size and shape of the bag. A unisex style is great for men, boys, women, and girls. This page has several handpicked options to choose from. If you like canvas, leather, or designer one strap backpacks you are going to find them here as well.