Update: The code below worked only on iOS7.
As Rickles said, you don't need to tweak the text to be localized. But just in case, someone has every reason for this, here is the code:
NSArray *activityItems = @[@"Test"]; UIActivityViewController *activityController = [[UIActivityViewController alloc] initWithActivityItems:activityItems applicationActivities:nil]; NSAttributedString *as = [[NSAttributedString alloc] initWithString:@"Custom Text" attributes:@{NSForegroundColorAttributeName:[UIColor greenColor]}]; [[UIButton appearanceWhenContainedIn:[UIActivityViewController class], nil] setAttributedTitle:as forState:UIControlStateNormal]; [self presentViewController:activityController animated:YES completion:nil];

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