Today while working on Reveal I became aware of a bug in iOS 7's UITextView's handling of the UITextInputTraits protocol.
The UITextInputTraits protocol has methods for setting what sort of keyboard
should be shown when a user taps on a UITextView and other such things.
iOS 7 also introduced a new selectable property on UITextView for controlling whether
text selection is enabled.  This is much better than the methods required in previous 
releases of iOS, where you had to subclass UITextView and return no for 
canBecomeFirstResponder or alternatively set an inputDelegate and
handle the appropriate delegate callbacks to stop selection for occurring.
Unfortunately, setting both editable and selectable to NO in iOS 7 breaks all of the
UITextInputTraits methods.  If you attempt to call any of them your app will crash 
with an instance does not respond to selector exception.  Which is weird because the 
UITextView instance will return YES if you call respondsToSelector: for any of the
methods declared in the UITextInputTraits protocol.
This appears to me to be a bug in iOS 7. I've reported it to Apple as radar://15063164.
I've also noticed that for UITextView's created via code (rather than in Storyboards) this bug 
doesn't express. I'm not sure why yet. There may be additional properties at work or 
the fact that the UITextView is initialised via initWithCoder: rather than 
initWithFrame: and may be in a different state due to this.
Some code that shows the bug:
@interface IBAViewController ()
@property (strong, nonatomic) IBOutlet UITextView *editableAndSelectable;
@property (strong, nonatomic) IBOutlet UITextView *selectable;
@property (strong, nonatomic) IBOutlet UITextView *notEditableOrSelectable;
@end
@implementation IBAViewController
- (void)viewDidLoad
{
    [super viewDidLoad];
    /* 
     Remove the define below and we won't crash on the last NSAssert below.  Leave it in
     and we crash (assuming we've created and connected three UITextView's to the IBOutlets above
     in a storyboard for this view controller).
    */
#define USING_STORYBOARD
#ifndef USING_STORYBOARD
    self.editableAndSelectable = [[UITextView alloc] initWithFrame:self.view.bounds];
    self.selectable = [[UITextView alloc] initWithFrame:self.view.bounds];
    self.notEditableOrSelectable = [[UITextView alloc] initWithFrame:self.view.bounds];
    [self.view addSubview:self.editableAndSelectable];
    [self.view addSubview:self.selectable];
    [self.view addSubview:self.notEditableOrSelectable];
#endif
    self.editableAndSelectable.text = @"Text1";
    self.editableAndSelectable.editable = YES;
    self.editableAndSelectable.selectable = YES;
    self.selectable.text = @"Text2";
    self.selectable.editable = NO;
    self.selectable.selectable = YES;
    self.notEditableOrSelectable.text = @"Text3";
    self.notEditableOrSelectable.editable = NO;
    self.notEditableOrSelectable.selectable = NO;
    NSAssert(self.editableAndSelectable.editable == YES, @"Huh?");
    NSAssert(self.editableAndSelectable.selectable == YES, @"Huh?");
    NSAssert([self.editableAndSelectable respondsToSelector:@selector(isSecureTextEntry)], @"Huh?");
    NSAssert([self.editableAndSelectable isSecureTextEntry] == NO, @"Huh?");
    NSAssert(self.selectable.editable == NO, @"Huh?");
    NSAssert(self.selectable.selectable == YES, @"Huh?");
    NSAssert([self.editableAndSelectable respondsToSelector:@selector(isSecureTextEntry)], @"Huh?");
    NSAssert([self.editableAndSelectable isSecureTextEntry] == NO, @"Huh?");
    NSAssert(self.notEditableOrSelectable.editable == NO, @"Huh?");
    NSAssert(self.notEditableOrSelectable.selectable == NO, @"Huh?");
    NSAssert([self.notEditableOrSelectable respondsToSelector:@selector(isSecureTextEntry)], @"Huh?");
    NSAssert([self.notEditableOrSelectable isSecureTextEntry] == NO, @"Huh?"); // crashes here (on iOS 7)
}
@end
Has anyone else seen this? Or have any ideas?