Brave Frontier needs to be online or have internet connection due to the following reasons:
- Handle the Social Feature or aspect of the game such as; Friend Invites, Sharing, Live News Update, Events and many more.
- Live Interaction with other Players in Raid Battle and Guild Raid Battle
- Handle or do In-App Purchases (IAP)
- Downloadable Content (DLC)
- Facebook Link and Update
Based on the following reasons above, it is imperative that you should always have a stable internet connection or connectivity and more so if you are using 3G/4G/LTE since it heavily relies on clear signal from each respective networks.
If you have any issues in the following features or content mentioned above, you can always try to do Basic Troubleshooting.