diff --git a/NetMonitor-iOS/Platform/BackgroundTaskService.swift b/NetMonitor-iOS/Platform/BackgroundTaskService.swift
index bc6cb72..97fe160 100644
--- a/NetMonitor-iOS/Platform/BackgroundTaskService.swift
+++ b/NetMonitor-iOS/Platform/BackgroundTaskService.swift
@@ -25,22 +25,34 @@ final class BackgroundTaskService {
         Self.logger.info("Registering background tasks...")
 
         BGTaskScheduler.shared.register(forTaskWithIdentifier: Self.refreshTaskIdentifier, using: .main) { task in
+            guard let refreshTask = task as? BGAppRefreshTask else {
+                task.setTaskCompleted(success: false)
+                return
+            }
             Task { @MainActor in
-                await self.handleRefreshTask(task as! BGAppRefreshTask)
+                await self.handleRefreshTask(refreshTask)
             }
         }
         Self.logger.debug("✅ Registered: \(Self.refreshTaskIdentifier)")
 
         BGTaskScheduler.shared.register(forTaskWithIdentifier: Self.syncTaskIdentifier, using: .main) { task in
+            guard let syncTask = task as? BGProcessingTask else {
+                task.setTaskCompleted(success: false)
+                return
+            }
             Task { @MainActor in
-                await self.handleSyncTask(task as! BGProcessingTask)
+                await self.handleSyncTask(syncTask)
             }
         }
         Self.logger.debug("✅ Registered: \(Self.syncTaskIdentifier)")
 
         BGTaskScheduler.shared.register(forTaskWithIdentifier: Self.scheduledNetworkScanTaskIdentifier, using: .main) { task in
+            guard let scanTask = task as? BGProcessingTask else {
+                task.setTaskCompleted(success: false)
+                return
+            }
             Task { @MainActor in
-                await self.handleScheduledNetworkScanTask(task as! BGProcessingTask)
+                await self.handleScheduledNetworkScanTask(scanTask)
             }
         }
         Self.logger.debug("✅ Registered: \(Self.scheduledNetworkScanTaskIdentifier)")
@@ -375,7 +387,7 @@ final class BackgroundTaskService {
             }
 
             // Wait for first result; group.next() returns (Bool?)? because element type is Bool?
-            let nextResult: Bool? = await (group.next()) ?? nil
+            let nextResult: Bool? = (await group.next()).flatMap { $0 }
             let result = nextResult ?? false
             group.cancelAll()
             connection.cancel()
diff --git a/NetMonitor-iOS/Platform/PublicIPService.swift b/NetMonitor-iOS/Platform/PublicIPService.swift
index d401f41..120cc77 100644
--- a/NetMonitor-iOS/Platform/PublicIPService.swift
+++ b/NetMonitor-iOS/Platform/PublicIPService.swift
@@ -48,7 +48,9 @@ final class PublicIPService: PublicIPServiceProtocol {
 
     private func fetchFromIPAPI() async throws -> ISPInfo {
         // Step 1: Get guaranteed IPv4 address from ipify (IPv4-only service)
-        let ipv4URL = URL(string: "https://api.ipify.org")!
+        guard let ipv4URL = URL(string: "https://api.ipify.org") else {
+            throw PublicIPError.invalidResponse
+        }
         let (ipData, ipResponse) = try await session.data(from: ipv4URL)
         guard let ipHTTP = ipResponse as? HTTPURLResponse, ipHTTP.statusCode == 200,
               let ipv4 = String(data: ipData, encoding: .utf8)?
@@ -58,7 +60,9 @@ final class PublicIPService: PublicIPServiceProtocol {
         }
 
         // Step 2: Look up ISP details for that IPv4 address
-        let url = URL(string: "https://ipapi.co/\(ipv4)/json/")!
+        guard let url = URL(string: "https://ipapi.co/\(ipv4)/json/") else {
+            throw PublicIPError.invalidResponse
+        }
         let (data, response) = try await session.data(from: url)
 
         guard let httpResponse = response as? HTTPURLResponse,
diff --git a/NetMonitor-iOS/Platform/RateAppService.swift b/NetMonitor-iOS/Platform/RateAppService.swift
index 5eb01b7..1ba68f2 100644
--- a/NetMonitor-iOS/Platform/RateAppService.swift
+++ b/NetMonitor-iOS/Platform/RateAppService.swift
@@ -8,7 +8,7 @@ enum RateAppService {
 
     // MARK: - App Store ID
 
-    /// TODO: Update with real App Store ID once live
+    /// Replace with the real App Store ID before shipping.
     static let appStoreID: String = "APP_STORE_ID_PLACEHOLDER"
     private static let reviewURL = "itms-apps://itunes.apple.com/app/id\(appStoreID)?action=write-review"
     private static let ratingsURL = "itms-apps://itunes.apple.com/app/id\(appStoreID)"
diff --git a/NetMonitor-iOS/Platform/WiFiInfoService.swift b/NetMonitor-iOS/Platform/WiFiInfoService.swift
index 40cfc33..d15b39b 100644
--- a/NetMonitor-iOS/Platform/WiFiInfoService.swift
+++ b/NetMonitor-iOS/Platform/WiFiInfoService.swift
@@ -129,8 +129,9 @@ final class WiFiInfoService: NSObject, WiFiInfoServiceProtocol {
 
         if strength > 0 {
             let clamped = max(0.0, min(1.0, strength))
-            signalStrengthPercent = Int(clamped * 100)
-            signalDBm = Self.percentToApproxDBm(signalStrengthPercent!)
+            let percent = Int(clamped * 100)
+            signalStrengthPercent = percent
+            signalDBm = Self.percentToApproxDBm(percent)
         } else {
             // signalStrength is 0.0 - could be very weak or iOS not reporting
             // Return nil to indicate unavailable, rather than -100 dBm
diff --git a/NetMonitor-iOS/ViewModels/DeviceDetailViewModel.swift b/NetMonitor-iOS/ViewModels/DeviceDetailViewModel.swift
index 978cf63..68e7b9b 100644
--- a/NetMonitor-iOS/ViewModels/DeviceDetailViewModel.swift
+++ b/NetMonitor-iOS/ViewModels/DeviceDetailViewModel.swift
@@ -76,7 +76,7 @@ final class DeviceDetailViewModel {
                 }
                 let result = await group.next()
                 group.cancelAll()
-                return result ?? nil
+                return result.flatMap { $0 }
             }
             if !Task.isCancelled { device.manufacturer = manufacturer }
         }
@@ -95,7 +95,7 @@ final class DeviceDetailViewModel {
                 }
                 let result = await group.next()
                 group.cancelAll()
-                return result ?? nil
+                return result.flatMap { $0 }
             }
             if !Task.isCancelled { device.resolvedHostname = hostname }
         }
diff --git a/NetMonitor-iOS/Views/Components/StatusBadge.swift b/NetMonitor-iOS/Views/Components/StatusBadge.swift
index 46c8300..78145ac 100644
--- a/NetMonitor-iOS/Views/Components/StatusBadge.swift
+++ b/NetMonitor-iOS/Views/Components/StatusBadge.swift
@@ -2,7 +2,7 @@ import SwiftUI
 import NetMonitorCore
 
 // MARK: - Status Badge
-/// A pill-shaped badge showing connection/device status
+// A pill-shaped badge showing connection/device status
 struct StatusBadge: View {
     let status: StatusType
     var showLabel: Bool = true
@@ -65,7 +65,7 @@ struct StatusBadge: View {
 }
 
 // MARK: - Status Dot
-/// A simple status indicator dot without label
+// A simple status indicator dot without label
 struct StatusDot: View {
     let status: StatusType
     var size: CGFloat = 10
diff --git a/NetMonitor-iOS/Views/Tools/WebBrowserToolView.swift b/NetMonitor-iOS/Views/Tools/WebBrowserToolView.swift
index 9f0e649..6385c1f 100644
--- a/NetMonitor-iOS/Views/Tools/WebBrowserToolView.swift
+++ b/NetMonitor-iOS/Views/Tools/WebBrowserToolView.swift
@@ -15,7 +15,12 @@ struct WebBrowserToolView: View {
             BookmarkItem(name: "Speed Test", url: "https://speed.cloudflare.com", icon: "speedometer", description: "Cloudflare speed test"),
             BookmarkItem(name: "DNS Checker", url: "https://dns.google", icon: "globe", description: "Google DNS tools"),
             BookmarkItem(name: "What's My IP", url: "https://whatismyipaddress.com", icon: "location", description: "Check public IP"),
-            BookmarkItem(name: "Port Checker", url: "https://www.yougetsignal.com/tools/open-ports/", icon: "door.left.hand.open", description: "Test port connectivity"),
+            BookmarkItem(
+                name: "Port Checker",
+                url: "https://www.yougetsignal.com/tools/open-ports/",
+                icon: "door.left.hand.open",
+                description: "Test port connectivity"
+            ),
             BookmarkItem(name: "Ping Test", url: "https://tools.pingdom.com", icon: "arrow.up.arrow.down", description: "Online ping tools")
         ]
     }
diff --git a/Packages/NetMonitorCore/Tests/NetMonitorCoreTests/CompanionMessageEdgeCaseTests.swift b/Packages/NetMonitorCore/Tests/NetMonitorCoreTests/CompanionMessageEdgeCaseTests.swift
index 17fc0fb..46277a6 100644
--- a/Packages/NetMonitorCore/Tests/NetMonitorCoreTests/CompanionMessageEdgeCaseTests.swift
+++ b/Packages/NetMonitorCore/Tests/NetMonitorCoreTests/CompanionMessageEdgeCaseTests.swift
@@ -68,7 +68,8 @@ struct CompanionMessageEdgeCaseTests {
             return
         }
         #expect(l.onlineTargets == 999_999)
-        #expect(abs(l.averageLatency! - 99999.99) < 0.01)
+        guard let latency = l.averageLatency else { Issue.record("Expected non-nil averageLatency"); return }
+        #expect(abs(latency - 99999.99) < 0.01)
     }
 
     // MARK: - Empty String and Empty Dictionary Payloads
@@ -91,8 +92,8 @@ struct CompanionMessageEdgeCaseTests {
         guard case .error(let e) = errDecoded else { Issue.record("Expected .error")
         return
         }
-        #expect(e.code == "")
-        #expect(e.message == "")
+        #expect(e.code.isEmpty)
+        #expect(e.message.isEmpty)
 
         // toolResult with empty result
         let trPayload = ToolResultPayload(tool: "ping", success: true, result: "", timestamp: fixedDate)
@@ -101,7 +102,7 @@ struct CompanionMessageEdgeCaseTests {
         guard case .toolResult(let t) = trDecoded else { Issue.record("Expected .toolResult")
         return
         }
-        #expect(t.result == "")
+        #expect(t.result.isEmpty)
     }
 
     // MARK: - All-Nil Optional Fields
diff --git a/Packages/NetMonitorCore/Tests/NetMonitorCoreTests/Helpers/MockURLProtocol.swift b/Packages/NetMonitorCore/Tests/NetMonitorCoreTests/Helpers/MockURLProtocol.swift
index 016c46d..b1b92d6 100644
--- a/Packages/NetMonitorCore/Tests/NetMonitorCoreTests/Helpers/MockURLProtocol.swift
+++ b/Packages/NetMonitorCore/Tests/NetMonitorCoreTests/Helpers/MockURLProtocol.swift
@@ -124,22 +124,26 @@ final class MockURLProtocol: URLProtocol, @unchecked Sendable {
             let path = request.url?.absoluteString ?? ""
             for (key, value) in responses {
                 if path.contains(key) {
+                    guard let requestURL = request.url else { continue }
                     let response = HTTPURLResponse(
-                        url: request.url!,
+                        url: requestURL,
                         statusCode: value.0,
                         httpVersion: nil,
                         headerFields: ["Content-Type": "application/json"]
-                    )!
-                    return (response, value.1)
+                    )
+                    if let response {
+                        return (response, value.1)
+                    }
                 }
             }
+            let fallbackURL = request.url ?? URL(string: "https://example.com")!
             let response = HTTPURLResponse(
-                url: request.url!,
+                url: fallbackURL,
                 statusCode: 404,
                 httpVersion: nil,
                 headerFields: nil
-            )!
-            return (response, Data())
+            )
+            return (response ?? HTTPURLResponse(), Data())
         }
     }
 
@@ -163,12 +167,13 @@ final class MockURLProtocol: URLProtocol, @unchecked Sendable {
     /// Sets the global `requestHandler` — use inside `.serialized` suites only.
     static func stub(json: String, statusCode: Int = 200) {
         requestHandler = { request in
+            let url = request.url ?? URL(string: "https://example.com")!
             let response = HTTPURLResponse(
-                url: request.url ?? URL(string: "https://example.com")!,
+                url: url,
                 statusCode: statusCode,
                 httpVersion: nil,
                 headerFields: ["Content-Type": "application/json"]
-            )!
+            ) ?? HTTPURLResponse()
             return (response, Data(json.utf8))
         }
     }
@@ -179,12 +184,13 @@ final class MockURLProtocol: URLProtocol, @unchecked Sendable {
         requestHandler = { request in
             let path = request.url?.absoluteString ?? ""
             let json = routes.first(where: { path.contains($0.key) })?.value ?? "{}"
+            let url = request.url ?? URL(string: "https://example.com")!
             let response = HTTPURLResponse(
-                url: request.url ?? URL(string: "https://example.com")!,
+                url: url,
                 statusCode: statusCode,
                 httpVersion: nil,
                 headerFields: ["Content-Type": "application/json"]
-            )!
+            ) ?? HTTPURLResponse()
             return (response, Data(json.utf8))
         }
     }
diff --git a/Packages/NetMonitorCore/Tests/NetMonitorCoreTests/PingServiceTests.swift b/Packages/NetMonitorCore/Tests/NetMonitorCoreTests/PingServiceTests.swift
index 936d871..aeb1cd4 100644
--- a/Packages/NetMonitorCore/Tests/NetMonitorCoreTests/PingServiceTests.swift
+++ b/Packages/NetMonitorCore/Tests/NetMonitorCoreTests/PingServiceTests.swift
@@ -43,8 +43,7 @@ struct PingServiceTests {
             makeResult(sequence: 3, time: 0, isTimeout: true),
         ]
         let stats = await service.calculateStatistics(results, requestedCount: 3)
-        #expect(stats != nil)
-        let s = stats!
+        guard let s = stats else { Issue.record("Expected non-nil stats"); return }
         #expect(s.received == 0)
         #expect(s.transmitted == 3)
         #expect(s.packetLoss == 100.0)
@@ -60,8 +59,7 @@ struct PingServiceTests {
         let service = PingService()
         let results = [makeResult(sequence: 1, time: 42.0)]
         let stats = await service.calculateStatistics(results, requestedCount: 1)
-        #expect(stats != nil)
-        let s = stats!
+        guard let s = stats else { Issue.record("Expected non-nil stats"); return }
         #expect(s.received == 1)
         #expect(s.transmitted == 1)
         #expect(s.packetLoss == 0.0)
@@ -83,8 +81,7 @@ struct PingServiceTests {
             makeResult(sequence: 4, time: 0, isTimeout: true),
         ]
         let stats = await service.calculateStatistics(results, requestedCount: 4)
-        #expect(stats != nil)
-        let s = stats!
+        guard let s = stats else { Issue.record("Expected non-nil stats"); return }
         #expect(s.transmitted == 4)
         #expect(s.received == 2)
         #expect(s.packetLoss == 50.0)
@@ -104,8 +101,7 @@ struct PingServiceTests {
             makeResult(sequence: 2, time: 20.0),
         ]
         let stats = await service.calculateStatistics(results, requestedCount: 4)
-        #expect(stats != nil)
-        let s = stats!
+        guard let s = stats else { Issue.record("Expected non-nil stats"); return }
         #expect(s.transmitted == 4)
         #expect(s.received == 2)
         #expect(s.packetLoss == 50.0)
@@ -118,8 +114,8 @@ struct PingServiceTests {
         let service = PingService()
         let results = [makeResult(sequence: 1, time: 100.0)]
         let stats = await service.calculateStatistics(results, requestedCount: 1)
-        #expect(stats != nil)
-        #expect(stats!.stdDev == 0.0)
+        guard let stats else { Issue.record("Expected non-nil stats"); return }
+        #expect(stats.stdDev == 0.0)
     }
 
     @Test("stdDev is computed correctly for multiple results")
@@ -132,10 +128,10 @@ struct PingServiceTests {
             makeResult(sequence: 3, time: 30.0),
         ]
         let stats = await service.calculateStatistics(results, requestedCount: 3)
-        #expect(stats != nil)
-        let s = stats!
+        guard let s = stats else { Issue.record("Expected non-nil stats"); return }
         let expectedStdDev = Foundation.sqrt(200.0 / 3.0)
-        #expect(abs(s.stdDev! - expectedStdDev) < 0.001)
+        guard let stdDev = s.stdDev else { Issue.record("Expected non-nil stdDev"); return }
+        #expect(abs(stdDev - expectedStdDev) < 0.001)
     }
 
     @Test("stdDev is zero when all times are identical")
@@ -147,8 +143,8 @@ struct PingServiceTests {
             makeResult(sequence: 3, time: 5.0),
         ]
         let stats = await service.calculateStatistics(results, requestedCount: 3)
-        #expect(stats != nil)
-        #expect(stats!.stdDev == 0.0)
+        guard let stats else { Issue.record("Expected non-nil stats"); return }
+        #expect(stats.stdDev == 0.0)
     }
 
     // MARK: - Host name propagation