diff --git a/README.md b/README.md
index 869ace5..953856e 100644
--- a/README.md
+++ b/README.md
@@ -254,11 +254,12 @@ Only available on Android and iOS.
 
 #### PickFilesOptions
 
-| Prop           | Type                  | Description                                                                                                                                                                                                                       | Default            |
-| -------------- | --------------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------------------ |
-| **`types`**    | <code>string[]</code> | List of accepted file types. Look at [IANA Media Types](https://www.iana.org/assignments/media-types/media-types.xhtml) for a complete list of standard media types. This option cannot be used with `multiple: true` on Android. |                    |
-| **`multiple`** | <code>boolean</code>  | Whether multiple files may be selected.                                                                                                                                                                                           | <code>false</code> |
-| **`readData`** | <code>boolean</code>  | Whether to read the file data.                                                                                                                                                                                                    | <code>false</code> |
+| Prop                   | Type                  | Description                                                                                                                                                                                                                       | Default            |
+| ---------------------- | --------------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------------------ |
+| **`types`**            | <code>string[]</code> | List of accepted file types. Look at [IANA Media Types](https://www.iana.org/assignments/media-types/media-types.xhtml) for a complete list of standard media types. This option cannot be used with `multiple: true` on Android. |                    |
+| **`customExtensions`** | <code>string[]</code> | iOS only. List of custom file name extensions (without leading dot '.'). Necessary in iOS since custom mimetypes are not supported. Example: `['cs2']`                                                                            |                    |
+| **`multiple`**         | <code>boolean</code>  | Whether multiple files may be selected.                                                                                                                                                                                           | <code>false</code> |
+| **`readData`**         | <code>boolean</code>  | Whether to read the file data.                                                                                                                                                                                                    | <code>false</code> |
 
 
 #### PickMediaOptions
diff --git a/ios/Plugin/FilePicker.swift b/ios/Plugin/FilePicker.swift
index 3611631..effb768 100644
--- a/ios/Plugin/FilePicker.swift
+++ b/ios/Plugin/FilePicker.swift
@@ -4,6 +4,7 @@ import Photos
 import Capacitor
 import UIKit
 import MobileCoreServices
+import UniformTypeIdentifiers
 
 @objc public class FilePicker: NSObject {
     private var plugin: FilePickerPlugin?
@@ -96,6 +97,17 @@ import MobileCoreServices
             }
         }
     }
+    
+    @available(iOS 14.0, *)
+    public func openDocumentPickerWithFileExtensions(multiple: Bool, documentTypes: [UTType]) {
+        DispatchQueue.main.async {
+            let documentPicker = UIDocumentPickerViewController(forOpeningContentTypes: documentTypes)
+            documentPicker.delegate = self
+            documentPicker.allowsMultipleSelection = multiple
+            documentPicker.modalPresentationStyle = .fullScreen
+            self.plugin?.bridge?.viewController?.present(documentPicker, animated: true, completion: nil)
+        }
+    }
 
     public func getPathFromUrl(_ url: URL) -> String {
         return url.absoluteString
diff --git a/ios/Plugin/FilePickerPlugin.swift b/ios/Plugin/FilePickerPlugin.swift
index b5f3320..0f5d170 100644
--- a/ios/Plugin/FilePickerPlugin.swift
+++ b/ios/Plugin/FilePickerPlugin.swift
@@ -2,6 +2,7 @@ import Foundation
 import Capacitor
 import UIKit
 import MobileCoreServices
+import UniformTypeIdentifiers
 
 /**
  * Please read the Capacitor iOS Plugin Development Guide
@@ -53,10 +54,20 @@ public class FilePickerPlugin: CAPPlugin {
 
         let multiple = call.getBool("multiple", false)
         let types = call.getArray("types", String.self) ?? []
-        let parsedTypes = parseTypesOption(types)
-        let documentTypes = parsedTypes.isEmpty ? ["public.data"] : parsedTypes
-
-        implementation?.openDocumentPicker(multiple: multiple, documentTypes: documentTypes)
+        let fileExtensions = call.getArray("customExtensions", String.self) ?? []
+        if #available(iOS 14.0, *) {
+            let parsedTypes = parseTypesOptionsToUTTypes(types)
+            let parsedExtensions = parseCustomExtensions(fileExtensions)
+            let concatenatedTypes = parsedTypes + parsedExtensions
+            let documentTypes = concatenatedTypes.isEmpty ? [.data] : concatenatedTypes
+            implementation?.openDocumentPickerWithFileExtensions(multiple: multiple, documentTypes: documentTypes)
+        } else {
+            // Fallback on earlier versions
+            let parsedTypes = parseTypesOption(types)
+            let documentTypes = parsedTypes.isEmpty ? ["public.data"] : parsedTypes
+
+            implementation?.openDocumentPicker(multiple: multiple, documentTypes: documentTypes)
+        }
     }
 
     @objc func pickImages(_ call: CAPPluginCall) {
@@ -94,6 +105,30 @@ public class FilePickerPlugin: CAPPlugin {
         return parsedTypes
     }
 
+    @available(iOS 14.0, *)
+    @objc func parseTypesOptionsToUTTypes(_ types: [String]) -> [UTType] {
+        var parsedTypes: [UTType] = []
+        for (_, type) in types.enumerated() {
+            guard let utType: UTType = UTType(mimeType: type) else {
+                continue
+            }
+            parsedTypes.append(utType)
+        }
+        return parsedTypes
+    }
+
+    @available(iOS 14.0, *)
+    @objc func parseCustomExtensions(_ extensions: [String]) -> [UTType] {
+        var parsedExtensions: [UTType] = []
+        for (_, exten) in extensions.enumerated() {
+            guard let utType: UTType = UTType(filenameExtension: exten) else {
+                continue
+            }
+            parsedExtensions.append(utType)
+        }
+        return parsedExtensions
+    }
+
     @objc func handleDocumentPickerResult(urls: [URL]?, error: String?) {
         guard let savedCall = savedCall else {
             return
@@ -107,9 +142,18 @@ public class FilePickerPlugin: CAPPlugin {
             return
         }
         let readData = savedCall.getBool("readData", false)
+        for (url) in urls {
+            guard url.startAccessingSecurityScopedResource() else {
+                return
+            }
+        }
         do {
             var result = JSObject()
             let filesResult = try urls.map {(url: URL) -> JSObject in
+                guard url.startAccessingSecurityScopedResource() else {
+                    let error = NSError(domain: "", code: 0, userInfo: [NSLocalizedDescriptionKey: "File access denied"])
+                    throw error
+                }
                 var file = JSObject()
                 if readData == true {
                     file["data"] = try implementation?.getDataFromUrl(url) ?? ""
@@ -130,6 +174,7 @@ public class FilePickerPlugin: CAPPlugin {
                 file["name"] = implementation?.getNameFromUrl(url) ?? ""
                 file["path"] = implementation?.getPathFromUrl(url) ?? ""
                 file["size"] = try implementation?.getSizeFromUrl(url) ?? -1
+                url.stopAccessingSecurityScopedResource()
                 return file
             }
             result["files"] = filesResult
diff --git a/src/definitions.ts b/src/definitions.ts
index b012481..acc7d66 100644
--- a/src/definitions.ts
+++ b/src/definitions.ts
@@ -81,6 +81,12 @@ export interface PickFilesOptions {
    * @example ['image/png', 'application/pdf']
    */
   types?: string[];
+  /**
+   * iOS only. List of custom file name extensions (without leading dot '.'). Necessary in iOS since custom mimetypes are not supported.
+   *
+   * Example: `['cs2']`
+   */
+  customExtensions?: string[];
   /**
    * Whether multiple files may be selected.
    *