My first reaction to the news of this app was, "well, that's silly." But it seems to have become ...a thing. Controversy. Whatever.
To those equating using the app as parents "abdicating responsibility," I would say I see it as another tool if they want to use it. Like putting locks on your doors, or blocking certain sites from your home computer, or not subscribing to cable channels with content you don't like. But I tend to favor letting parents make their own parenting choices, even if I don't agree with them. Unless it is profoundly or permanently damaging to the child or contrary to public health and safety, I generally tread carefully in condemning others' parenting choices.
On the author's/creator's rights side, I have more mixed feelings and I am not exactly clear on how the app works. If the site is altering the book without author approval
before it is sold & delivered to the consumer, that is a problem for me. If the app somehow takes an existing file that the consumer owns,* and is truly only filtering what is displayed, I have fewer problems.
I would prefer it black out or replace with **** any "objectionable" words than ham-fistedly substituting from a pre-set list. What if a character is named Jesus (Hay-soos)? What if a preacher character is telling someone they need to change their ways or be damned? Lot less effective than telling them they'll be darned! What if someone is saying, "stop being such a dick!"? Now it'll be the much better, "stop being such a groin!"!
If it's truly just filtering or editing software that an end-user implements on only their copy of the book for their own use, I really have no objections to that in concept. It's little different than using available tools to add/switch covers, copyedit to personal standards, change fonts and formatting, etc. If someone wants to manually use existing tools to change/expurgate/bowdlerize a book, they can. This app just seems to make that simpler and automated.
Personally, I disagree with the necessity or impetus to do so. Plenty of other options are available and have been discussed. Read another book. Discuss the book in context with your child. Etc. But, as a general concept, I think the end user has a right to do this. But it does come back to my general precept about many of our legal "rights": Just because you have
the right to do something doesn't make it the
right thing to do.
But from what I am seeing, I don't think this is all in the end user's hands. There seems to be at least some of the alterations going on in the site/seller's hands. That
is a problem.
*And please, let's not open the owned vs. licensed discussion/debate. That's a separate topic. For my purposes, once you purchase an ebook, you morally/ethically have certain rights to alter that file for your own personal use.