Influence is a measure of your core progression through Single City and is a key part of your total House Points, which determines how you measure up against other players in the game!

To increase Influence, you can do the following:

• Upgrade Rooms in your House!
• Upgrade furniture in your House!
• Move in and grow your Roomies!
• Complete research in Single City Academy!

Influence is unlootable so once you have it, no one can take it from you! Your Influence won’t decrease unless you unequip furniture from your House.'

How do I check how much Influence I have?

Tap on Phone at the bottom right hand of your screen. Go to the Trending page. Tap on the little 'i' icon next to Trending, and there you'll see a breakdown of your House Points into Followers and Influence!

According to this screenshot, this user has 858, 857, 600 Influence! Wowza!