How can I upgrade the OS of my Samsung Galaxy Exhibit from Android 4.1 to 4.4 or higher? How can I upgrade the OS of my Samsung Galaxy Exhibit (SGH-T599N) from Android 4.1 to 4.4 or higher?

I am trying to install Live on YouTube – by Xperia on my smartphone so that I can live stream videos on YouTube, but it's giving me this error message: "This app is incompatible with your device." 

According to the app's Google Play homepage, which was updated last week, the app requires Android 4.4 or higher. I only have 4.1. :( So, I assumed it must be because of that (please correct me if this assumption might be wrong.) Also, when I press Software Update on my device, I get: "This device is up to date." Could it mean that I may never be able to update it anymore because it's too old?
Android updates are issued per device. Once the device is selected for update the update is distributed OTA(Over The Air) from your wireless carrier. Until then you have to use the current installed version of the OS.