If there’s one app that manages to combine ‘taste graph’ opinion-sharing with simplicity, ease of use and fun, it’s Amen. Now the Berlin-based startup behind it is set to roll out version 1.5 of the app with significant new features, while it announces fresh funding from Sunstone Capital and Path’s Dave Morin, adding to the likes of Ashton Kutcher and SoundCloud’s founders, who are already on board.

Amen is based around a simple premise – you share an opinion e.g., ‘Apple Strudel is the best dessert ever’ and others either agree with it by selecting ‘Amen!’ or disagree with a ‘Hell No!’, requiring them to offer an alternative suggestion (maybe they prefer cherry pie, for example). It’s a simple but addictive premise that, over time, builds up rich data about the opinions of its users. The new version of Amen, which goes live tomorrow, promises to maintain that simplicity while enriching it with additional features.

Firstly, you can now add pictures to posts, so if you want to show off ‘The cutest kitten ever’ or the ‘The best sunrise ever’, go right ahead.

amen1 Addictive opinion app Amen adds media and social features, new investment from Sunstone and Dave Morin amen2 Addictive opinion app Amen adds media and social features, new investment from Sunstone and Dave Morin

There’s also richer support for music, meaning that hundreds of millions of songs are recognised when you discuss them, and you can even listen to a 30-second preview and buy the song from iTunes right from the app. This should make music-based debates even more fun.

Sometimes you want to debate the topic of an Amen discussion in a bit more depth than simply agreeing or disagreeing, and the new app will allow you to comment on any post. Additionally, there’s Facebook timeline support, with real-time information on your opinions able to be shared to the Ticker within Facebook.

Staying with Facebook, Amen now has the ability to recognise when you’re discussing Facebook friends. This allows Amen to tie a discussion to specific people, where relevant “Jane Smith is the best sales director in the whole world” – now Amen can know which Jane Smith that is and share a message to their wall. This creates a neat viral marketing opportunity but it’s clearly a smart enhancement to Amen’s pool of data too.

amen3 Addictive opinion app Amen adds media and social features, new investment from Sunstone and Dave Morin amen4 Addictive opinion app Amen adds media and social features, new investment from Sunstone and Dave Morin

When we predicted 5 startup trends for 2012, ‘the battle for the opinion graph’ was one that seemed particularly likely to take off. The new version of Amen’s app sets it up nicely in this respect. It’s potentially even more fun than before, while providing an even richer mass of data about the aggregate opinions of its users. Indeed, CEO Felix Peterson says that Amen is seeing “industry leading retention and activity numbers.”

Perhaps that’s why Amen has been able to expand its seed round by $1m, to a total of $2.9m, via fresh investment from Denmark’s Sunstone Capital. Dave Morin’s Slow Ventures has also got on-board as an angel investor. They join Index (Danny Rimer); A Grade (Ashton Kutcher, Ron Burkle, Guy Oseary); Christophe Maire, and SoundCloud founders Alexander Ljung and Eric Wahlforss in backing this German startup that you really do need to keep your eye on this year.

The new version of the iPhone app goes live on the App Store tomorrow morning, European time.

See also: our interview with Amen CEO Felix Petersen last October.

➤ Amen – App Store link