diff --git a/iOS/AppDefaults.swift b/iOS/AppDefaults.swift
index 98c59261a..be4de2a08 100644
--- a/iOS/AppDefaults.swift
+++ b/iOS/AppDefaults.swift
@@ -11,6 +11,7 @@ import UIKit
 struct AppDefaults {
 
 	struct Key {
+		static let lastImageCacheFlushDate = "lastImageCacheFlushDate"
 		static let firstRunDate = "firstRunDate"
 		static let timelineGroupByFeed = "timelineGroupByFeed"
 		static let timelineNumberOfLines = "timelineNumberOfLines"
@@ -27,6 +28,15 @@ struct AppDefaults {
 		return true
 	}()
 	
+	static var lastImageCacheFlushDate: Date? {
+		get {
+			return date(for: Key.lastImageCacheFlushDate)
+		}
+		set {
+			setDate(for: Key.lastImageCacheFlushDate, newValue)
+		}
+	}
+
 	static var refreshInterval: RefreshInterval {
 		get {
 			let rawValue = UserDefaults.standard.integer(forKey: Key.refreshInterval)
@@ -74,7 +84,8 @@ struct AppDefaults {
 	}
 	
 	static func registerDefaults() {
-		let defaults: [String : Any] = [Key.refreshInterval: RefreshInterval.everyHour.rawValue,
+		let defaults: [String : Any] = [Key.lastImageCacheFlushDate: Date(),
+										Key.refreshInterval: RefreshInterval.everyHour.rawValue,
 										Key.timelineGroupByFeed: false,
 										Key.timelineNumberOfLines: 3,
 										Key.timelineSortDirection: ComparisonResult.orderedDescending.rawValue]
diff --git a/iOS/AppDelegate.swift b/iOS/AppDelegate.swift
index d74176d9d..912675902 100644
--- a/iOS/AppDelegate.swift
+++ b/iOS/AppDelegate.swift
@@ -178,12 +178,31 @@ private extension AppDelegate {
 	private func initializeDownloaders() {
 		let tempDir = FileManager.default.urls(for: .cachesDirectory, in: .userDomainMask).first!
 		let faviconsFolderURL = tempDir.appendingPathComponent("Favicons")
+		let imagesFolderURL = tempDir.appendingPathComponent("Images")
+		let homePageToIconURL = tempDir.appendingPathComponent("HomePageToIconURLCache.plist")
+
+		// If the image disk cache hasn't been flushed for 3 days and the network is available, delete it
+		if let flushDate = AppDefaults.lastImageCacheFlushDate, flushDate.addingTimeInterval(3600*24*3) < Date() {
+			if let reachability = try? Reachability(hostname: "apple.com") {
+				if reachability.connection != .unavailable {
+					for tempItem in [faviconsFolderURL, imagesFolderURL, homePageToIconURL] {
+						do {
+							os_log(.info, log: self.log, "Removing cache file: %@", tempItem.absoluteString)
+							try FileManager.default.removeItem(at: tempItem)
+						} catch {
+							os_log(.error, log: self.log, "Could not delete cache file: %@", error.localizedDescription)
+						}
+					}
+					AppDefaults.lastImageCacheFlushDate = Date()
+				}
+			}
+		}
+		
 		try! FileManager.default.createDirectory(at: faviconsFolderURL, withIntermediateDirectories: true, attributes: nil)
 		let faviconsFolder = faviconsFolderURL.absoluteString
 		let faviconsFolderPath = faviconsFolder.suffix(from: faviconsFolder.index(faviconsFolder.startIndex, offsetBy: 7))
 		faviconDownloader = FaviconDownloader(folder: String(faviconsFolderPath))
 		
-		let imagesFolderURL = tempDir.appendingPathComponent("Images")
 		let imagesFolder = imagesFolderURL.absoluteString
 		let imagesFolderPath = imagesFolder.suffix(from: imagesFolder.index(imagesFolder.startIndex, offsetBy: 7))
 		try! FileManager.default.createDirectory(at: imagesFolderURL, withIntermediateDirectories: true, attributes: nil)