Artpoli Gallery+ for iPhone (and iPod touch) has just been launched. With + version, which is priced at $1.99, you can save the images to use as wallpapers, etc. The no + version, priced at $0.99, does not allow saving outside the app.
We have some promo codes, with which you can download Artpoli Gallery for free. If you like to have this, let me know. You can have either + or no + version, but I guess the + dominates when both are free.