Is Plex the only option to stream from a PC to a smartphone/tablet?

I'd love to get fully involved with Plex, but there are router/port issues that I can't seem to get around.

Not sure why it's so difficult but it is and I don't really have the time to tweak my router.

There has to be other viable options for streaming from a local PC to a remote device. By remote I mean on different networks in different locations. (Space limitations remove Dropbox, Skydrive, etc as options)

I've looked up and down the Play store but nothing seems to stand out.