Caution - long post. TL : DR - main differences between all the different types of mod and APV that I could think of.
There are fixed voltage ego style batteries that are similar to your EVOD. These are good batteries to simply screw something in to and vape. You have no control over the power being delivered to your topper though and so you have to be careful as to the resistance of the coil head you use.
Then there are VV/VW (variable voltage / variable wattage) ego style batteries like the Spinner II and the Joye Twist. These both have built in batteries that range from 200mAh (barely an hour of normal vaping time) all the way up to 2000mAh which should last all but the heaviest vaper a full day. They also mostly charge with a screw in charger that connects to the top of the battery, where the topper screws in. They often do not have screens but you can change the power delivered to the topper with a simple twist of a dial on the bottom of the battery. I would call these beginner to intermediate devices. (although there are some veterans that still use them because they do a great job in a small form)
Then you have box mods that have a built in battery, like the MVP2, iStick and a few others. These usually have a larger battery than the ego type batteries. The iStick is really small even though it's a box - no taller than a bic lighter and about twice as wide. These charge with a micro USB that connects to the base of the battery usually allowing you to continue to vape while they charge. Again, you can change the power output on these devices and almost everyone can find a good vape with them.
There are some of the higher watt box mods that take replaceable batteries. This means you have to remove the batteries and put them in your own charger to charge. Something like a Sigelei 100w or similar is in this catagory and they have a lot of power. Just to confuse the issue there are also box mods that take replaceable batteries that you can charge with a micro USB charger - think IPV type box mods. I would call these intermediate to advanced devices although a beginner can use them successfully with some reading and education about them and how to use them safely.
Then there are mechanical tubes. These have no circuit board on them and are powered with a replaceable battery. You have no real control over the power delivered to your device other than changing the resistance of the topper. I would consider these intermediate to advanced devices as it usually means using a topper that you have to build the coil yourself - although you can screw in a Nautilus and get a reasonable vape. Of course, you also need a separate charger and batteries for these devices. Mechanical boxes are the same theory as the tube mechanical - but in a box shape. Something like a REO would fall in to this catagory. Mechanical devices need to be used in a safe manner as you can get yourself in trouble quickly if you don't build your coil correctly or use the wrong type of battery. Further reading and learning will be necessary for most people before jumping in to mech(anical)s Some examples are Nemisis, SMPL, Panzer etc.
Finally there are regulated tubes that almost always take replaceable batteries and have circuitry that allows you to select the power being delivered to your device. They almost always have screens that give you information about the vape you are getting. Some examples are Vamo, Innokin VV3 / VV4, eVic, Provari etc.
I'm sure I have forgotten some important details and will leave it to other to pick holes / suggest other devices / set me right
