diff --git a/AlphaWallet/AddMultipleCustomRpc/AddMultipleCustomRpcView.swift b/AlphaWallet/AddMultipleCustomRpc/AddMultipleCustomRpcView.swift
index 764a9be84..c797ba95a 100644
--- a/AlphaWallet/AddMultipleCustomRpc/AddMultipleCustomRpcView.swift
+++ b/AlphaWallet/AddMultipleCustomRpc/AddMultipleCustomRpcView.swift
@@ -28,11 +28,7 @@ class AddMultipleCustomRpcView: UIView {
 
     private lazy var activityIndicatorView: UIActivityIndicatorView = {
         let view: UIActivityIndicatorView
-        if #available(iOS 13.0, *) {
-            view = UIActivityIndicatorView(style: .medium)
-        } else {
-            view = UIActivityIndicatorView(style: .white)
-        }
+        view = UIActivityIndicatorView(style: .medium)
         view.translatesAutoresizingMaskIntoConstraints = false
         view.hidesWhenStopped = false
         return view
diff --git a/AlphaWallet/AppCoordinator.swift b/AlphaWallet/AppCoordinator.swift
index 3464a162f..2880dc0c5 100644
--- a/AlphaWallet/AppCoordinator.swift
+++ b/AlphaWallet/AppCoordinator.swift
@@ -299,7 +299,6 @@ class AppCoordinator: NSObject, Coordinator {
     }
 
     func handleIntent(userActivity: NSUserActivity) -> Bool {
-        guard #available(iOS 12.0, *) else { return false }
         if let type = userActivity.userInfo?[WalletQrCodeDonation.userInfoType.key] as? String, type == WalletQrCodeDonation.userInfoType.value {
             analyticsService.log(navigation: Analytics.Navigation.openShortcut, properties: [
                 Analytics.Properties.type.rawValue: Analytics.ShortcutType.walletQrCode.rawValue
diff --git a/AlphaWallet/Core/Device.swift b/AlphaWallet/Core/Device.swift
index eec36c90d..29bc29384 100644
--- a/AlphaWallet/Core/Device.swift
+++ b/AlphaWallet/Core/Device.swift
@@ -232,8 +232,6 @@ extension UIDevice {
     }
 
     static public var isSafeAreaDevice: Bool {
-        // above iOS11 dont have safe area
-        guard #available(iOS 11.0, *) else { return false }
         guard let safeAreaInsets = UIApplication.shared.firstKeyWindow?.safeAreaInsets else {
             return false
         }
diff --git a/AlphaWallet/Core/SwapToken/HoneySwap/HoneySwap.swift b/AlphaWallet/Core/SwapToken/HoneySwap/HoneySwap.swift
index d4db3fbd7..452be34c0 100644
--- a/AlphaWallet/Core/SwapToken/HoneySwap/HoneySwap.swift
+++ b/AlphaWallet/Core/SwapToken/HoneySwap/HoneySwap.swift
@@ -105,14 +105,10 @@ class HoneySwap: TokenActionsProvider, SwapTokenURLProviderType {
 
 extension UITraitCollection {
     var honeyswapTheme: HoneySwap.Theme {
-        if #available(iOS 12.0, *) {
-            switch userInterfaceStyle {
-            case .dark:
-                return .dark
-            case .light, .unspecified:
-                return .light
-            }
-        } else {
+        switch userInterfaceStyle {
+        case .dark:
+            return .dark
+        case .light, .unspecified:
             return .light
         }
     }
diff --git a/AlphaWallet/Core/SwapToken/Uniswap/Uniswap.swift b/AlphaWallet/Core/SwapToken/Uniswap/Uniswap.swift
index 98d18b8fb..d62cef678 100644
--- a/AlphaWallet/Core/SwapToken/Uniswap/Uniswap.swift
+++ b/AlphaWallet/Core/SwapToken/Uniswap/Uniswap.swift
@@ -112,14 +112,10 @@ struct Uniswap: TokenActionsProvider, SwapTokenURLProviderType {
 
 extension UITraitCollection {
     var uniswapTheme: Uniswap.Theme {
-        if #available(iOS 12.0, *) {
-            switch userInterfaceStyle {
-            case .dark:
-                return .dark
-            case .light, .unspecified:
-                return .light
-            }
-        } else {
+        switch userInterfaceStyle {
+        case .dark:
+            return .dark
+        case .light, .unspecified:
             return .light
         }
     }
diff --git a/AlphaWallet/Donations/WalletQrCodeDonation.swift b/AlphaWallet/Donations/WalletQrCodeDonation.swift
index 38467c0aa..39fdf1547 100644
--- a/AlphaWallet/Donations/WalletQrCodeDonation.swift
+++ b/AlphaWallet/Donations/WalletQrCodeDonation.swift
@@ -27,7 +27,6 @@ class WalletQrCodeDonation {
     }
 
     func donate() {
-        guard #available(iOS 12.0, *) else { return }
         let activity = NSUserActivity(activityType: Self.activityType)
         activity.title = R.string.localizable.donateShortcutsWalletQrCode()
         let walletKey = "wallet"
@@ -41,11 +40,10 @@ class WalletQrCodeDonation {
     }
 
     func delete() {
-        guard #available(iOS 12.0, *) else { return }
         info("Deleting donated shortcut: \(Self.persistentIdentifier)…")
         CSSearchableIndex.default().deleteSearchableItems(withDomainIdentifiers: [Self.persistentIdentifier])
         NSUserActivity.deleteSavedUserActivities(withPersistentIdentifiers: [Self.persistentIdentifier]) {
             info("Deleted donated shortcut: \(Self.persistentIdentifier)")
         }
     }
-}
\ No newline at end of file
+}
diff --git a/AlphaWallet/Rpc Network/AvailableRpcNetwork.swift b/AlphaWallet/Rpc Network/AvailableRpcNetwork.swift
index 52027dd28..ea4dd5d3a 100644
--- a/AlphaWallet/Rpc Network/AvailableRpcNetwork.swift	
+++ b/AlphaWallet/Rpc Network/AvailableRpcNetwork.swift	
@@ -81,12 +81,8 @@ fileprivate func readFileIntoMemory(url: URL) -> Data? {
 
 fileprivate func uncompressData(data: Data) -> Data? {
     do {
-        if #available(iOS 13.0, *) {
-            let uncompressedData = try (data as NSData).decompressed(using: selectedCompressionAlgorithm)
-            return uncompressedData as Data
-        } else {
-            return nil
-        }
+        let uncompressedData = try (data as NSData).decompressed(using: selectedCompressionAlgorithm)
+        return uncompressedData as Data
     } catch {
         return nil
     }
diff --git a/AlphaWallet/Style/AppStyle.swift b/AlphaWallet/Style/AppStyle.swift
index 16f1bad61..754c38e99 100644
--- a/AlphaWallet/Style/AppStyle.swift
+++ b/AlphaWallet/Style/AppStyle.swift
@@ -377,11 +377,7 @@ enum Style {
     enum TabBar {
         enum Background {
             static let color: UIColor = {
-                if #available(iOS 13.0, *) {
-                    return UIColor.systemBackground
-                } else {
-                    return R.color.white()!
-                }
+                return UIColor.systemBackground
             }()
         }
         enum Separator {
diff --git a/AlphaWallet/TokenScriptClient/Coordinators/EventSourceCoordinator.swift b/AlphaWallet/TokenScriptClient/Coordinators/EventSourceCoordinator.swift
index 8385fab2a..657d3b34c 100644
--- a/AlphaWallet/TokenScriptClient/Coordinators/EventSourceCoordinator.swift
+++ b/AlphaWallet/TokenScriptClient/Coordinators/EventSourceCoordinator.swift
@@ -18,7 +18,7 @@ extension PromiseKit.Result {
 
 protocol EventSourceCoordinatorType: class {
     func fetchEthereumEvents()
-    func fetchEventsByTokenId(forToken token: TokenObject) -> [Promise<Void>]
+    @discardableResult func fetchEventsByTokenId(forToken token: TokenObject) -> [Promise<Void>]
 }
 
 //TODO rename this generic name to reflect that it's for event instances, not for event activity
diff --git a/AlphaWallet/Tokens/Collectibles/Views/AssetsPageView.swift b/AlphaWallet/Tokens/Collectibles/Views/AssetsPageView.swift
index 158048982..c000a02ac 100644
--- a/AlphaWallet/Tokens/Collectibles/Views/AssetsPageView.swift
+++ b/AlphaWallet/Tokens/Collectibles/Views/AssetsPageView.swift
@@ -188,12 +188,7 @@ extension AssetsPageView: StatefulViewController {
 extension UICollectionViewLayout {
     static func createGridLayout(spacing: CGFloat = 16, heightDimension: CGFloat = 220) -> UICollectionViewLayout {
         let layout = UICollectionViewCompositionalLayout { _, _ -> NSCollectionLayoutSection? in
-            let iosVersionRelatedFractionalWidthForGrid: CGFloat
-            if #available(iOS 13.0, *) {
-                iosVersionRelatedFractionalWidthForGrid = 1.0
-            } else {
-                iosVersionRelatedFractionalWidthForGrid = 0.92
-            }
+            let iosVersionRelatedFractionalWidthForGrid: CGFloat = 1.0
 
             let itemSize = NSCollectionLayoutSize(widthDimension: .fractionalWidth(1.0), heightDimension: .fractionalHeight(1.0))
             let item = NSCollectionLayoutItem(layoutSize: itemSize)