Analog refers to the "old school" systems that use a switch box in the cabin that sends high current DC signal to electrically operated solenoid valves that control air entering and exiting the air springs. The amount of air pressure is controlled by the amount of time the user activates the switch. This technology was/is often found on mini trucks and hot rods because the large valves allow a large volume of air to move quickly.
Manual refers to a system that incorporates four cockpit mounted "paddle valves" that mechanically switch air flow from the tank in-to or out-of the air springs. This cost-effective system has very simple electrical connections, and is the most lightweight of the three types. It also includes two dual-needle air pressure gauges to monitor and set pressures. If simplicity and low cost is high on your list of requirements, this is your system.
Digital management brings to the game a whole level of sophistication and features. As the name suggests, there is an ECU that uses digital intelligence in the form of an algorithm to quickly and accurately move your suspension to the desired setting with no driver involvement besides pressing a button. Our Autopilot V2 system includes a compact manifold unit that contains the ECU, all the valves, and pressure sensors that monitor and activate the suspension, along with an OEM level wiring harness that only requires 3 wires to be connected to the vehicle. The interface for this hardware is a cockpit mounted controller that provides 8 unique user programmable presets. For the most convenience and flexibility, this is the system to have.