Lock screens. They're very important to some HTC EVO users and hugely bothersome to others. Regardless of your take on the matter, there is no disputing that HTC has carved out a small niche with the lock screen capabilities on devices preloaded Sense 3.0 as well as on certain custom ROMs for the EVO 4G that sport some of the elements of Sense 3.0.
By now you have seen countless videos and write-ups that explain that you can customize the app shortcuts shown on your lock screen. You may not, however, have noticed a small detail that could give you a headache.
With the release of Android 2.2, users have been able to move apps to and run them from their SD cards. Due to space and memory limitations on the device itself, most of us have become accustomed to moving nearly every app we can to the card. This is where I found the Sense 3.0 lock screen wrinkle.
Any application you wish to access via your flashy new lock screen must reside on the phone's internal memory, or you will end up with the same empty space some users experienced with the disappearing phone icon.
I discovered this on my EVO 4G after some trial and error, thinking it had to do with the custom ROM I'd flashed. But then I found the same to be true once I migrated to the EVO 3D.
One additional tidbit: Users who opt to run LauncherPro, ADW, and other third-party home launchers will have to switch back to HTC Sense to make any changes to the lock screen. Just clear your defaults (Settings > Applications > Manage applications > All > HTC Sense > Clear defaults) and return to Sense to make the adjustments. Once completed, go right on back to the land of docks and hidden icon labels (my main reasons for opting out of Sense).