Well, apps can do everything nowadays so here are my ideas:

• A translation app (more efficient than Google Translator)
• An app which enables people to get in contact if they want some translations (for instance: I could offer my help as I'm a teacher)
• Snapchat / Instagram to be rewarded for posting pictures
• Twitch could be linked to Steemit : we could reward players of video games immediately via lives on Steemit (like a partnership between the two websites)