Can it take 220v or just 110v?

It is 110-220v capable, with an AC adapter and a wall plug.

Do you know if it retains its most recent color/brightness settings if powered off then back on?

Yes, it will retain its most recent color/brightness settings.

Are the bulbs exposed on the backside?

No, the bulbs are not exposed on the backside.

Which side does the cord come out of?

The cord is on the right side. 

Is it compatible with Alexa, Google, Apple Home?

No, it is not compatible with Alexa, Google Home, or Apple Home.

Are bulbs replaceable?

The LED is embedded. It is not replaceable but normally lasts 50,000 hours.

Does this put out any heat? How far from furniture do you recommend?

It emits barely any heat. You can put it close to the furniture, if you want.

Does it light up a room like a floor lamp would?

Yes, but if you put the light source toward the corner of the wall, it might not be as bright as a traditional floor lamp.

Is there an app that can control this lamp?

No, there is no app that can be used to control the lamp.

Does it change colors?

Yes, you can use the remote to change colors.

Is it dimmable?

Yes, it is dimmable.

Is the vertical member one piece and not a two piece connection?

It is a one-piece connection, but it is remotely controlled. The remote control can control 2 or 3 lamps at the same time. Hence, you don't have to connect each lamp together.

How do you turn it on and off?

You turn it on and off with the remote control.

Does it only have have colors or can it do white light?

The easy to use remote control makes it simple to shuffle through 16+ million colors and 300+ multi-color effects to find your perfect lighting.

Can it be powered by a 12 volt source, opposed to adapted 120 volt?

Yes, you can use 12V, 2 A, or 3A volt source.

How tall is it?

It is 55" inches tall.

If you get 3+ lamps, will one remote control all of them?

Yes, you can control all lamps with one remote control at the same time.