My marriage definitely benefits when I take tiny bits of time to tell my wife I'm thinking about her. For example:

- Text her a random emoji

- Email her an image I've found (usually using our app Prism http://www.steamclocksw.com/prism/)

- Send her a Draw Something drawing

The point is to send a "unit of thinking about you" that's simple but unique enough that it's not mechanical (like a "poke" would be). Pair seems like it could bring this little habit to more relationships, or at least displace text and email for those who do this.