The Surface
Some have a grudge at the elite "because they leave us here to rot." while others have the ambition to climb up to this land of opportunity. This exodus of the rich created a great division between rich and poor though. With the rich parting from the surface development needed to follow them because research needs money, thus only the idealistic researcher stays behind. Yet that is not much. Thus the surface fell into decay and almost returned to the stone age, certainly when the fossil fuel sources dried up and cars where of no more use.
The surface dwellers, ‘compassionately’ called Dustbiters by the Skylanders, have thus needed to rely on physical strength a lot more, doing things by foot or by bike mostly, though some might use a paraglide or hot-air balloons like that. But when there’s no wind that has little effect. This makes their appearance more robust then their above land counterparts.
The surface dwellers have since depletion of fossil fuel sources started to cut trees for fire to get energy. This has the effect that there are only a few patches of forest left, which cannot take all the pollution. The air became toxic and the surface dwellers have to wear a form of filter/gasmask when outside. People are starting to replant patches of forest as there is more space for trees now that the elite moved up. But that will still take some time to grow, and large areas of the sky have the sun blocked out by the Skyland cities overhead. The Skyland cities are domed and filter the air coming in.
Skyland
The elite, with their scientists who had foreseen this had already, after decent research implemented the use of another source of energy, one that did not dry up, the sun. Using their technology they could send solar panels into the sky because of the solar kites. These solar kites did not use much energy while in the mean time charging batteries and feeding power to the city below.
The Skylanders, just as ‘compassionately’ called Airheads by the surface dwellers, don’t need to rely on force, since everything is done for them by electronics. This results in 2 distinct postures. One part of the population is fat and out of condition, feasting on the possibilities to have all they want within hand’s reach. Others are thin, as they gain no muscle but don’t eat unhealthy either. They eat supplements. Something like the next-gen vitamins, capsules or goo that has everything in itself that the body needs to be healthy. Both of these forms can be here because the rich guys will want the comfort and get fat, while the scientists will on the other hand try to perfect the health of the body. Only the police and military forces are somewhat more muscular, but still not much, since they are in suits that give more power and that give the ability to fly (or hover) and need to be as light as possible to cut down energy us of the suits. It’s also the police/military forces that have special forces called the Wired.
The wired
The Wired have wires in their body that can connect to electrical devices. In some way they can control how these wires move (they are linked to nerve systems or something?). First they where applied to the hands, but limiting the use of the hands otherwise there had been quickly decided that shoulders, backs and torso's, the head and neck were better alternatives since your hands are free to drink coffee in the mean time, or keep typing while managing different systems at the mean time or have a weapon if needed. (To stun, kill or sedate the guards with the gun while you are wired to the safe, cracking its digital lock or something).
Applications could vary. You could be the hub to connect different systems or you could wire yourself to a device completely controlling it through your mind or nerve system or something other appropriate. This could be a major computer, a building (with security camera's (with a link to your eyes or several screens or your helmet)) or an entire mobile suit. When you power something it will cost you energy, but if the thing powers itself you will only spend energy as if you do other things normally (thinking, walking, ...). There are also Battery Packs to which you can wire yourself.