The Jade plant looks like it may have scale insects. Are the spots like bumps in any way, or are they flat and just a color difference? If they are like small bumps, I would guess that your succulent has attracted some scale bugs. Scale bugs are annoying little things that like to eat the sap out of your succulents. It may seem like they are little black spots, but if it is scale insects, then they are actually little insects with outer shells that shield them from pesticides and predators. If there are only a few bumps, you can scratch them off with your fingernail, but if there are a lot, I would advise removing the infected leaves. You could also dab them with some rubbing alcohol on a cotton swab to dissolve the shells which will eventually kill them. If the plants are outdoor plants, you can buy live ladybugs and release them to feed on the soft shelled scale insects.

-Hope this helps! But it may not be scale bugs, check if they are little bumps that you can scrape off. Here is an image of what scale bugs look like, see if that's what your look like:

Oedema may look like 'pimples' too. Kylie posted photo with what does look like scale.

Scale will come off quite easy if you take q-tip or cotton ball moistened with rubbing alcohol and wipe across (or scrape as she suggested...I just don't like the goo). Scale would be also quite regular round or oval, while oedema could be just pimple-like or bigger spots.

If you need to force to get them off - scrape hard, and that leaves hole in the flesh - it may be oedema.