I was originally skeptical of Periscope, an app that lets you post a live video cast, but I've totally fallen in love with it. It actually reminds me of snapchat because the raw, unfiltered video feels very authentic, and it's ephemeral too (you can choose whether to have videos available for replay; regardless they're deleted within 24 hours).
Unlike snapchat (or really, anything), it sends a push notification when someone you're following starts casting. Surprisingly, it's not annoying: I think the live video experience is really valuable. I was laying in bed once and saw my friend running across the Golden Gate Bridge, and it felt so cool to see this true idea of what Katherine was doing right now, and to ask her questions that she would answer in real time.
Swaypay
The Twenty Minute VC