. here is an "app" that I've found handy to have available on my phones (I've had it for my last three iPhones). For a doubler like me (who doesn't spend much time on the bundle of sticks each year, it will save your bacon more than a few times. It's called Bassoon (duh!), and it's for the more or less standard Heckel bassinet to low Bb. The method of scanning through the notes is smooth, and the visual presentation of the key work is minimalist while still being crystal-clear. And, the price (as is the case with most iPhone applications) is right. Search the App Store and you will turn it up. Incidentally, the name Bassoon calls to mind the fact that we have a street named 'Bassoon Street' here in Houston. I've even seen high school players posing under the street sign, ungainly horn in hand, for a photo being taken by mom or dad. Sadly, there is no street named 'Bass Clarinet Terrace'