I couldn't figure out why my Note3 wasn't installing any apps until this: A great post in the Verizon Note3 forum:
still doesn't work for me..."failed to install app"...
I was having the exact same problem with my Gear 2 where I couldn't install ANY apps no matter what! I tried the optional link above in this post to the Samsung Apps but with no luck at all. Then, out of frustration I did a Factory Data Reset on my Note 3, as well as on my Gear 2 (which still didn't solve the problem), but THEN I installed the Samsung Apps from the link above, and that did the trick. Not only am I able to install apps now on my Gear 2, but the reset also helped with the connection back and forth between my Gear 1 and Gear 2. It appears that these devices prefer a "clean install" which helps them work much better, especially if you already had the Gear 1 and all it's software already installed.
After having the Gear 2 for two weeks now, I am finally able to do something with it. Before this, I could not get ANY notifications at all or install any apps, along with a few other problems which made my Gear 2 almost useless, so I had to try something. I spoke to Samsung tech support almost daily but they could never resolve the problems.
If all else is failing, try it.
Awesome news man! Congrats!