Simple: Keep your bags locked. No pickpocket is going to waste precious time trying to mess with a bag that is clearly locked. Even if it is poorly locked, you no longer look like a target because you have taken clear steps to protect yourself. The result is that the thief moves on to easier prey.
A rope or coil lock has many uses. You can fit this type of lock onto virtually any bag but it can also lock several items together, or several sections of your bag. You can use it to secure a camera while still being able to use it. Again, at Travel Gadget we strive to only use gadgets with multiple uses reducing the number of things to carry.
Travel Gadget Pro Tip: Looking like you're protected is almost as important as actually being secure. Place your most valuable and important items in the deepest center pocket and lock it up!