[straden]

Could anyone recommend me an app / program for iOS to be able to listen flac?
I've tried several but none of them works / crashes.
Mine is already jailbroken as well.

 

[MrProggie]

Some iPods can be rockboxed which enables flac playing.
iPhones are able to play lossless ALAC.
 
For jailbroken iphones/ipods, read this.

 

[shigzeo]

You could try VLC - it is free. I've not tried it on iOS for music playback, but on my home computer, it plays FLAC.

 

[straden]

But that vlc is for ipad... not iphone...

 

[j57park]

i remember having vlc4iphone (or something like that ) on my ipod touch 1st gen long time ago.
The usability was pretty bad but I only had 2 FLAC songs so no biggie.