Just to beat this horse one more time, having auto rotate active is a very desirable feature. I use this all the time with a Nexus 7 and Asus TF700 running Naviator. I use a home-made kneeboard with a swivel feature. When turning from a north-south heading to an east-west heading, I simply rotate the tablet from portrait to landscape. I have to lift my leg slightly for a second or two to cause the app to rotate. As an aside, I believe my tablets are functioning properly as I have tested them and they normally rotate at about 45 degrees.
I understand, some people would not want the rotate feature. It would be easy enough to provide a lock screen button in the IFly app. It's usually better to include features for those who want them than to exclude features for those who don't want them. Right now, the landscape mode is basically useless as is.