GearHub is one application for some Samsung Gear apps. You should download them from Samsung Apps manually.

It provides authorization internet and other data depending on application and wearable device model.

If you don't use one of supported apps you don't need it.

Supports Gear apps:
* ENoteGear (https://apps.samsung.com/gear/appDetail.as?appId=0j9JljHps4). Evernote client
* SocialGear (https://apps.samsung.com/gear/appDetail.as?appId=h97fP4q1rn). Vkontakte client
* SquareGear (https://apps.samsung.com/gear/appDetail.as?appId=mDnj2LjkID). FourSquare client
* TaskGear (https://apps.samsung.com/gear/appDetail.as?appId=NTX6vuNrli). Todoist client
* TodoGear (https://apps.samsung.com/gear/appDetail.as?appId=5gMZi7Z8Vp). Toodledo client.

If you have troubles with listed apps please do following steps:
1) Reboot both phone and watch
2) If nothing helps just uninstall GearHub and app from Gear reboot both devices and install again.
3) If you have troubles with login VKontakte please install official app

If this simple steps doesn't help please contact me and we'll try to solve problem together!