How do i get a gemini air if i already have service

Solid Signal has them for 199 dollars. You can get a Gemini box from Walmart for 45 bucks. 

I'm looking for an alternative to Roku stick with the DirecTV Stream app. the guide and Library episodes are hard to see when laying in bed with my Progressive vision.  Plus interested in finding out  if it is preferable to the Roku app user interface

Gemini box and Gemini air are both cable like experiences with remotes. If you like a device with remote where you can use numbers to change channels.......shortcut buttons for record, dvr list, previous channel, guide then this might be for you.