Electrical robotic pool vacuums contain a small, electrically powered pump that draws water off the pool floor along with dirt, leaves, bugs, etc.. The water passes through a filter element (usually cloth) that traps the debris and then proceeds out of a discharge port which propels the vacuum across the pool floor.
The main advantage of an electronic pool robot is convenience. The unit is entirely independent of any other pool equipment, so you do not have to spend any time disconnecting or reconnecting hoses. You simply clean the filter, plug the unit in and flip a switch. The robot does the rest.
The primary disadvantage of an electrical pool robot is cost. Some units can cost nearly $1,000. However, Intex pools are relatively small, so smaller, less expensive units are quite sufficient. Some that you may consider are the Pool Rover or Pool Rover Jr. Both of these units are often available on eBay or similar internet sites for $250-$400.
Another disadvantage of an electrical pool vacuum is that the filter element may not always capture small particles. Some algae or dust particles are small enough to slip through, so all you end up doing is stirring them up. However, this can be somewhat helpful since the suspended particles may eventually pass through your normal filtration system and get captured there.