There are a few Bird Journal Premium features that are only available on the Windows desktop software currently. This is something we are changing, starting with filters.
Filters are now available for both iOS and Android based devices. To get them, install the updated app from either the Apple AppStore or Google Play.
If you're not familiar with filters, they allow you to instantly filter entries and species screens by location, year, month, species or custom property. Just tap the filters row at the top of the relevant screen, pick some values and go back to the screen. You'll see the list of items update.
Other premium analysis features are Graphs, Maps and Photo Gallery. You can help us decide which should come first by voting on our feedback site using the links above.