Gianpiero Riva's smartphone images range from thought provoking landscapes to intimate portraits.

Gianpiero Riva, and electronic engineer living outside Venice, Italy, started using his iPhone camera like most people — taking snapshots of friends, family, daily life. After two years, what began as a hobby had turned into a book and a business.

Riva (@giariv) is the author of "Fotografia smartphone. Scatta, elabora, condividi," a 160-page book on smartphone photography. On top of his book project, him and his friends created JewelGram—a company that will take Instagram photos and put them on jewely. 

We spoke with Riva via email about his book, business and favorite images.

Connect: How did you get started in smartphone photography?

Riva: With Instagram. I discovered the app in Jan 2011… During the first three or four months I [had] been taking shots of my daily life without thinking too much. But then I found out that there was more under the hood. I found that there were real artists sharing their artworks. And I decided to see what might have happened with an iPhone and a bunch of creativity.

Among Riva's nearly one thousand Instagram photos, he picked this one out as his favorite. Taken during a media tour in Lebanon, this photo resonates with him. "I was moved by the fact that they were very poor… but in the meantime so happy," Riva said.

Your Instagram account has a wide variety of photos. (Landscapes, portraits, you seem to have it all!) How would you describe your photographic style? 

My style is that… I've not a style! I mean, many of my followers say I have a style and that is possible to recognize it even if i take photos of so many different subjects. But the very true thing is that I like to make experiments… so I often change subjects and editing techniques. Sometime I even try to emulate the style of other Instagramers.

I see you've written a book on smartphone photography. Can you tell me a little about it? 

"A very famous Italian publishing house (APOGEO of the Feltrinelli Group) asked me to write a book (the first one in Italy about this topic) about smartphone photography. Translated the title could sound like "Smartphone Photography - Shoot, edit, share."

JewelGram, founded by Riva and his friend Michele Marzotto, puts Instagram photos on jewelry.

I see you also are a cofounder of JewelGram. Where did that idea come from? 

The fairy tale says that some months ago two Instagram-addict friends, drinking some glasses of Prosecco di Valdobbiadene, were thinking about the fact that if it's true that "a diamond is forever" it's also true that "a picture is forever." It happens that one of those friends is a jewelry designer and the other one is an electronic engineer and software programmer. Some months later JewelGram was born. JewelGram makes jewels from your Instagram pictures.

The gifted designer of JewelGram is my old friend Michele Marzotto (@mkmrz8 on Instagram).

Here are a few of our favorite smartphone photos from Riva:

If you know an interesting mobile photographer who should be featured in our Exposure series, let us know: