Live TV price?

I signed up for Channels plus for $8 a month. Do I really need to pay $25 per device on top of that for the live TV app? That seems crazy, I assumed that was included.

It is. Download the "Channels DVR" app, which is free. However, the app will only function when paired with a Channels DVR server.

(That applies to all platforms except iOS. The regular Channels app was recently made free on iOS; the $25 Channels app on other platforms is still available, though.)

So lets say I'm away from home on vacation. I don't want to leave my PC/DVR server on for electricity reasons. But I occasionally want to watch live TV on my android device.

I can do that with the $25 channels live tv app? But not my $8 a month subscription?

No. The live TV version does not have the ability to stream from home. Channels DVR Server is what provides the ability to stream away from home.

I wouldn't worry much about electricity costs. About a week of it being on while away is probably less than $1.