ShotBlocker
Security and privacy
screenshot detection
SHOW HN2012
How HN took it
2 positive, 9 neutral or asking, 0 mixed, 15 critical, out of 26 comments about the project. Thread score -0.51.
Idea: 1 for, 11 againstPrivacy: 1 for, 2 againstPerformance: 0 for, 2 against
The thread, comment by comment
Each row is a top-level comment and its replies, in HN's order. Select a cell to open that comment on HN.
positive neutral or mixed critical about another commenter or something else the maker
What HN said
What people liked
Useful for apps that want to notify senders of screenshots as a UX feature.
From 2 comments
Yup, it's impossible to prevent or delete screenshots before they're taken (and you could also do something like take a photo of the device with another camera, if you really…
10char on HNWith apps like Facebook Poke or SnapChat the content you're sending is ephemeral (it won't be around forever). Developers of these types of apps can't necessarily prevent a…
thomasvendetta on HN
Objections
Cannot prevent screenshots; a second camera can still capture the screen.
From 3 comments
While this may be nice - it's only a partial solution. Anybody can take a photo of screen from device #1 with camera from device #2. Nothing can prevent that.
uptown on HNNothing would stop a second phone with its camera recording the footage of the first camera.
plasma on HNI'm not an iOS user, but what is to stop the user from taking a screenshot and storing it somewhere else? Or posting it to a remote server? Since the image on the screen is in…
jstanley on HN
Name is misleading since it doesn't block anything.
From 1 comment
Seems misleading to call this "ShotBlocker" when it doesn't actually block anything.
mikeash on HN
Detection relies on polling the photo library, which is a hack.
From 2 comments
iOS gives no access to these buttons. It looks as though this code just polls the photo library and checks if a new photo was created. There was a different version going around…
wattson12 on HNI do not believe the iOS SDK has access to these buttons. As other users have pointed out, screenshot detection is a hacky method of checking if touch interaction is temporarily…
prezjordan on HN
Raises concerns about user control over their own device and privacy.
From 2 comments
I don't deny there are issues, but they are societal/educational ones. People need to learn that when you send someone something, that's it, it's out of the bag, even if you…
npsimons on HNIs Apple approving spyware applications now? Is it the app's business what core OS functionality you're using behind its back?
jrockway on HN
Requests
Detect AirPlay mirroring as a screenshot-like leak.
From 1 comment
If you're trying to block screenshots, AirPlay mirroring is something else you'll likely want to watch for. It's possible to send a separate feed to the AirPlay display; but not…
ConstantineXVI on HN
Questions
Why would anyone need to block screenshots of an app?
From 1 comment
Can someone elaborate on why this is an issue? Why would you need to block screenshots of your app?
klapinat0r on HN
Alternatives named
Snapchat and Poke screenshot notifications.
From 2 comments
With apps like Facebook Poke or SnapChat the content you're sending is ephemeral (it won't be around forever). Developers of these types of apps can't necessarily prevent a…
thomasvendetta on HNYup, it's impossible to prevent or delete screenshots before they're taken (and you could also do something like take a photo of the device with another camera, if you really…
10char on HN
Steganographic watermarking of images.
From 1 comment
Would it not be so much easier to simply show images with some steganographic message ("I was displayed in SnapChat") in it, and just check for this rather than checking for…
oulipo on HN