I saw this Kickstarter for an item called "The Element" and figured I would share it. It's an item similar to AstroPrint (except better) where you can access your printer through WiFi and control printing. They're also going to integrate an option where you can monitor your print through a camera. It's compatible with Marlin and Repetier, so it will be compatible with the gMax. Anyways, check out the link, the project has 11 days left.
https://www.kickstarter.com/projects/printr/the-element-3d-printers-missing-element
https://www.kickstarter.com/projects/printr/the-element-3d-printers-missing-element