writes "With the latest news from Microsoft, which will allow open source apps in their store, we will see more and more an abundance of per-pay applications mixed with license-free ones. What if you can't tell between free and non-free anymore? Even now, a quick search on the Android market is just not telling enough. But what do you do then when Ubuntu has the same problem?"
For Android there's always the F-Droid market
that exclusively lists Free Software (it's small, but I've found it pretty useful).