(Reuters) - An app that acts like a musical postcard enables users to capture and share musical moments with friends and family and to discover great songs along the way.

Called Soundtracking, the free app lets users share song clips, along with their thoughts, location and a photo to help convey their experiences.

Music, like photos or paintings or any sort of creative art, has such a wide range of emotions that can be different for different people, said Steve Jang, CEO of Schematic Labs, the San-Francisco based company that created the app.

This idea of a story through song is what we wanted to share ... It really is this expressive musical postcard.

Jang believes it is the personalization that helps users filter through all the music being shared on social networks.

Just because you're listening to something doesn't mean you like it. It doesn't mean there's any sort of emotional or life importance to it. People perk up and listen more when you have that, he explained.

The app can autodetect the song that is playing in a room, and posts can also be shared on Facebook, Twitter and Foursquare.

Users can discover new music by viewing the content posted by others. A preview of the song is available for free, and a full version can be purchased in iTunes or through the music screening services Spotify or Rdio on Android devices.

Clicking on the map icon in a Soundtracking post reveals all posts that users have posted at that location.

Neighborhoods are interesting -- you can see the difference between Williamsburg, Brooklyn versus Upper East Side, Manhattan or Venice Beach, California versus Beverly Hills, Jang said.

The app has over 1 million users worldwide, with half in United States and the remainder in Western Europe, Canada and Japan, according to Jang, who added that users in different countries tend to use the app in different ways.

A lot of the Japanese users love to wake up and post 'Good Morning' songs and then do a 'Good Evening' song to all their friends and followers, he explained.

In Europe, a lot of users there love taking photos of the countryside or the urban landscape and then talking a little bit about how they feel emotionally.

Jang conceived the idea for the app two years ago while traveling through Europe.

I was thinking wouldn't it be great to be able to share easily what music you were listening to, or what was playing around you, while you were sitting on the train, taking a walk along a canal or in a great music cafe.

A similar app called Frenzapp is also available.