Mobility is the speed at which a Player can move with a certain weapon drawn out. The higher the mobilty, the faster the player can move. The slower the mobility, the more encumbered a player will be. Mobility techinically does not effect jumping, but a faster mobility will lead to farther jumps when performed.
In order to negate slow move speed created by weapons with low mobility (e.g. Sniper Rifles), the Player can pull out weapons/equipment with higher mobility (such as a Pistol, Melee Weapon, Grenade, etc.) to travel quickly through safe areas of a map.