How to Block Screenshots in iOS Apps Using AI
This Knowledge Base article describes how to use Appdome’s AI/ML in your CI/CD pipeline to continuously deliver plugins that Block Screen Shots in iOS apps.
What is Block Screenshots?
Block Screenshots a privacy feature for iOS applications that blurs the app’s screen when it is minimized and viewed in the multitasking switcher. This mechanism ensures that sensitive data, such as financial or personal information, is not visible when the app is in the background, safeguarding against unauthorized viewing or potential data leaks. This type of protection is essential in applications that handle confidential data, providing users with an extra layer of security by preventing screenshots or prying eyes from accessing sensitive content displayed in the app’s preview.
How Appdome Protects Mobile Apps with Block Screenshots?
Appdome’s dynamic Block Screenshots plugin applies an enhanced blur effect to the app’s screen when it is minimized and shown in the multitasking view. This ensures that sensitive data cannot be captured or viewed while the app is in the background. The feature is designed to be seamless and only activates when the app loses focus, providing a smooth user experience without sacrificing security.
Prerequisites for Using Appdome's Use Block Screen Shots Plugins:
To use Appdome’s mobile app security build system to Block Screen Shots , you’ll need:
- Appdome account (create a free Appdome account here)
- A license for Use Block Screen Shots
- Mobile App (.ipa for iOS)
- Signing Credentials (see Signing Secure Android apps and Signing Secure iOS apps)
How to Implement Block Screen Shots in iOS Apps Using Appdome
On Appdome, follow these 3 simple steps to create self-defending iOS Apps that Block Screen Shots without an SDK or gateway:
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Designate the Mobile App to be protected.
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Upload an app via the Appdome Mobile Defense platform GUI or via Appdome’s DEV-API or CI/CD Plugins.
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iOS Formats: .ipa
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Use Block Screen Shots is compatible with: Obj-C, Java, Swift, Flutter, React Native, Unity, Xamarin, Cordova and other iOS apps.
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Select the defense: Use Block Screen Shots.
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Follow the steps in Sections 2.2-2.2.2 of this article to add the Use Block Screen Shots feature to your Fusion Set via the Appdome Console.
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When you select the Use Block Screen Shots you'll notice that the Fusion Set you created in step 2.1 now bears the icon of the protection category that contains Use Block Screen Shots.
Figure 2: Fusion Set that displays the newly added Use Block Screen Shots protection
Note: Annotating the Fusion Set to identify the protection(s) selected is optional only (not mandatory). -
Open the Fusion Set Detail Summary by clicking the “...” symbol on the far-right corner of the Fusion Set. Copy the Fusion Set ID from the Fusion Set Detail Summary (as shown below):
Figure 3: Fusion Set Detail Summary
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Follow the instructions below to use the Fusion Set ID inside any standard mobile DevOps or CI/CD toolkit like Bitrise, Jenkins, Travis, Team City, Circle CI or other system:
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Refer to the Appdome API Reference Guide for API building instructions.
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Look for sample APIs in Appdome’s GitHub Repository.
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Create and name the Fusion Set (security template) that will contain the Use Block Screen Shots feature as shown below:Figure 1: Fusion Set that will contain the Use Block Screen Shots feature
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Add the Use Block Screen Shots feature to your security template.
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Navigate to Build > Anti ATO tab > Mobile Account Protection section in the Appdome Console.
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Toggle On > Use Block Screen Shots.
Figure 4: Selecting Block Screen Shots
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Congratulations! The Use Block Screen Shots protection is now added to the mobile app -
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Certify the Use Block Screen Shots feature in iOS Apps
After building Use Block Screen Shots, Appdome generates a Certified Secure™ certificate to guarantee that the Use Block Screen Shots protection has been added and is protecting the app. To verify that the Use Block Screen Shots protection has been added to the mobile app, locate the protection in the Certified Secure™ certificate as shown below:
Figure 5: Certified Secure™ certificate
Each Certified Secure™ certificate provides DevOps and DevSecOps organizations the entire workflow summary, audit trail of each build, and proof of protection that Use Block Screen Shots has been added to each iOS app. Certified Secure provides instant and in-line DevSecOps compliance certification that Use Block Screen Shots and other mobile app security features are in each build of the mobile app.
Using Threat-Events™ for Screen Shots Intelligence and Control in iOS Apps
Appdome Threat-Events™ provides consumable in-app mobile app attack intelligence and defense control when Screen Shots is detected. To consume and use Threat-Events™ for Screen Shots in iOS Apps, use AddObserverForName in Notification Center, and the code samples for Threat-Events™ for Screen Shots shown below.
The specifications and options for Threat-Events™ for Screen Shots are:
Threat-Event™ Elements | Block Screen Shots Method Detail |
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Appdome Feature Name | Use Block Screen Shots |
Threat-Event Mode | |
OFF, IN-APP DEFENSE | Appdome detects, defends and notifies user (standard OS dialog) using customizable messaging. |
ON, IN-APP DETECTION | Appdome detects the attack or threat and passes the event in a standard format to the app for processing (app chooses how and when to enforce). |
ON, IN-APP DEFENSE | Uses Appdome Enforce mode for any attack or threat and passes the event in a standard format to the app for processing (gather intel on attacks and threats without losing any protection). |
Certified Secure™ Threat Event Check | x |
Visible in ThreatScope™ | x |
Developer Parameters for Blocking Screen Shots Threat-Event™ | |
Threat-Event NAME | |
Threat-Event DATA | reasonData |
Threat-Event CODE | reasonCode |
Threat-Event REF | |
Threat-Event SCORE | |
currentThreatEventScore | Current Threat-Event score |
threatEventsScore | Total Threat-events score |
Threat-Event Context Keys | |
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message | Message displayed for the user on event |
failSafeEnforce | Timed enforcement against the identified threat |
externalID | The external ID of the event which can be listened via Threat Events |
osVersion | OS version of the current device |
deviceModel | Current device model |
deviceManufacturer | The manufacturer of the current device |
fusedAppToken | The task ID of the Appdome fusion of the currently running app |
kernelInfo | Info about the kernel: system name, node name, release, version and machine. |
deviceID | Current device ID |
reasonCode | Reason code of the occurred event |
buildDate | Appdome fusion date of the current application |
devicePlatform | OS name of the current device |
updatedOSVersion | Is the OS version up to date |
timeZone | Time zone |
deviceFaceDown | Is the device face down |
locationLong | Location longitude conditioned by location permission |
locationLat | Location latitude conditioned by location permission |
locationState | Location state conditioned by location permission |
wifiSsid | Wifi SSID |
wifiSsidPermissionStatus | Wifi SSID permission status |
threatCode | The last six characters of the threat code specify the OS, allowing the Threat Resolution Center to address the attack on the affected device. |
With Threat-Events™ enabled (turned ON), iOS developers can get detailed attack intelligence and granular defense control in iOS applications and create amazing user experiences for all mobile end users when Screen Shots is detected.
The following is a code sample for native iOS apps, which uses all values in the specification above for Use Block Screen Shots:
Important! Replace all placeholder instances of <Context Key> with the specific name of your threat event context key across all language examples. This is crucial to ensure your code functions correctly with the intended event data. For example, The <Context Key> could be the message, externalID, OS Version, reason code, etc.
x
let center = NotificationCenter.default
center.addObserver(forName: Notification.Name(""), object: nil, queue: nil) { (note) in
guard let usrInf = note.userInfo else {
return
}
let message = usrInf["message"]; // Message shown to the user
let reasonData = usrInf["reasonData"]; // Threat detection cause
let reasonCode = usrInf["reasonCode"]; // Event reason code
// Current threat event score
let currentThreatEventScore = usrInf["currentThreatEventScore"];
// Total threat events score
let threatEventsScore = usrInf["threatEventsScore"];
// Replace '<Context Key>' with your specific event context key
// let variable = usrInf["<Context Key>"];
// Your logic goes here (Send data to Splunk/Dynatrace/Show Popup...)
}
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[[NSNotificationCenter defaultCenter] addObserverForName: @"" object:nil queue:nil usingBlock:^(NSNotification *org_note) {
__block NSNotification *note = org_note;
dispatch_async(dispatch_get_main_queue(), ^(void) {
// Message shown to the user
NSString *message = [[note userInfo] objectForKey:@"message"];
// Threat detection cause
NSString *reasonData = [[note userInfo] objectForKey:@"reasonData"];
// Event reason code
NSString *reasonCode = [[note userInfo] objectForKey:@"reasonCode"];
// Current threat event score
NSString *currentThreatEventScore = [[note userInfo] objectForKey:@"currentThreatEventScore"];
// Total threat events score
NSString *threatEventsScore = [[note userInfo] objectForKey:@"threatEventsScore"];
// Replace '<Context Key>' with your specific event context key
// NSString *variable = [[note userInfo] objectForKey:@"<Context Key>"];
// Your logic goes here (Send data to Splunk/Dynatrace/Show Popup...)
});
}];
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const { ADDevEvents } = NativeModules;
const aDDevEvents = new NativeEventEmitter(ADDevEvents);
function registerToDevEvent(action, callback) {
NativeModules.ADDevEvents.registerForDevEvent(action);
aDDevEvents.addListener(action, callback);
}
export function registerToAllEvents() {
registerToDevEvent(
"",
(userinfo) => Alert.alert(JSON.stringify(userinfo))
var message = userinfo["message"] // Message shown to the user
var reasonData = userinfo["reasonData"] // Threat detection cause
var reasonCode = userinfo["reasonCode"] // Event reason code
// Current threat event score
var currentThreatEventScore = userinfo["currentThreatEventScore"]
// Total threat events score
var threatEventsScore = userinfo["threatEventsScore"]
// Replace '<Context Key>' with your specific event context key
// var variable = userinfo["<Context Key>"]
// Your logic goes here (Send data to Splunk/Dynatrace/Show Popup...)
);
}
x
RegisterReceiver(new ThreatEventReceiver(), new IntentFilter(""));
class ThreatEventReceiver : BroadcastReceiver
{
public override void OnReceive(Context context, Intent intent)
{
// Message shown to the user
String message = intent.GetStringExtra("message");
// Threat detection cause
String reasonData = intent.GetStringExtra("reasonData");
// Event reason code
String reasonCode = intent.GetStringExtra("reasonCode");
// Current threat event score
String currentThreatEventScore = intent.GetStringExtra("currentThreatEventScore");
// Total threat events score
String threatEventsScore = intent.GetStringExtra("threatEventsScore");
// Replace '<Context Key>' with your specific event context key
// String variable = intent.GetStringExtra("<Context Key>");
// Your logic goes here (Send data to Splunk/Dynatrace/Show Popup...)
}
}
x
NSNotificationCenter.DefaultCenter.AddObserver(
(NSString)"", // Threat-Event Identifier
delegate (NSNotification notification)
{
// Message shown to the user
var message = notification.UserInfo.ObjectForKey("message");
// Threat detection cause
var reasonData = notification.UserInfo.ObjectForKey("reasonData");
// Event reason code
var reasonCode = notification.UserInfo.ObjectForKey("reasonCode");
// Current threat event score
var currentThreatEventScore = notification.UserInfo.ObjectForKey("currentThreatEventScore");
// Total threat events score
var threatEventsScore = notification.UserInfo.ObjectForKey("threatEventsScore");
// Replace '<Context Key>' with your specific event context key
// var variable = notification.UserInfo.ObjectForKey("<Context Keys>");
// Your logic goes here (Send data to Splunk/Dynatrace/Show Popup...)
}
);
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window.broadcaster.addEventListener("", function(userInfo) {
var message = userInfo.message // Message shown to the user
var reasonData = userInfo.reasonData // Threat detection cause
var reasonCode = userInfo.reasonCode // Event reason code
// Current threat event score
var currentThreatEventScore = userInfo.currentThreatEventScore
// Total threat events score
var threatEventsScore = userInfo.threatEventsScore
// Replace '<Context Key>' with your specific event context key
// var variable = userInfo.<Context Keys>
// Your logic goes here (Send data to Splunk/Dynatrace/Show Popup...)
});
x
import 'dart:async';
import 'package:flutter/material.dart';
import 'package:flutter/services.dart';
class PlatformChannel extends StatefulWidget {
const PlatformChannel({super.key});
State<PlatformChannel> createState() => _PlatformChannelState();
}
class _PlatformChannelState extends State<PlatformChannel> {
// Replace with your EventChannel name
static const String _eventChannelName = "";
static const EventChannel _eventChannel = EventChannel(_eventChannelName);
void initState() {
super.initState();
_eventChannel.receiveBroadcastStream().listen(_onEvent, onError: _onError);
}
void _onEvent(Object? event) {
setState(() {
// Adapt this section based on your specific event data structure
var eventData = event as Map;
// Example: Accessing 'externalID' field from the event
var externalID = eventData['externalID'];
// Customize the rest of the fields based on your event structure
String message = eventData['message']; // Message shown to the user
String reasonData = eventData['reasonData']; // Threat detection cause
String reasonCode = eventData['reasonCode']; // Event reason code
// Current threat event score
String currentThreatEventScore = eventData['currentThreatEventScore'];
// Total threat events score
String threatEventsScore = eventData['threatEventsScore'];
// Replace '<Context Key>' with your specific event context key
// String variable = eventData['<Context Keys>'];
});
}
// Your logic goes here (Send data to Splunk/Dynatrace/Show Popup...)
}
Using Appdome, there are no development or coding prerequisites to build secured Apps by using Use Block Screen Shots. There is no SDK and no library to code or implement in the app and no gateway to deploy in your network. All protections are built into each app and the resulting app is self-defending and self-protecting.
Releasing and Publishing Mobile Apps with Use Block Screen Shots
After successfully securing your app by using Appdome, there are several available options to complete your project, depending on your app lifecycle or workflow. These include:
- Customizing, Configuring & Branding Secure Mobile Apps.
- Deploying/Publishing Secure mobile apps to Public or Private app stores.
- Releasing Secured Android & iOS Apps built on Appdome.
Related Articles:
- How to Build Enhanced App Screen Blur iOS Apps
- How to Protect iOS Apps from Screen Sharing Malware
- How to Protect Android & iOS Apps from Copy/Paste Attacks
How Do I Learn More?
If you have any questions, please send them our way at support.appdome.com or via the chat window on the Appdome platform.
Thank you!
Thanks for visiting Appdome! Our mission is to secure every app on the planet by making mobile app security easy. We hope we’re living up to the mission with your project.