GC3 Secondary Options

I want to purchase the gs3 panel. I also need a secondary panel in bedroom. will the TS1 work with the gs3?

No. The TS1 is not compatible with the GC3.

The GC3 is getting its own secondary touchscreen from 2GIG, but we do not have an ETA on when that will be released, unfortunately.

At the current time, only the PAD1 can be used as a secondary keypad.