diff --git a/Ably.podspec b/Ably.podspec
index bbd7ed856..75f7055a6 100644
--- a/Ably.podspec
+++ b/Ably.podspec
@@ -11,15 +11,17 @@ Pod::Spec.new do |s|
   s.source            = { :git => "/~https://github.com/ably/ably-ios.git", :tag => s.version.to_s }
   s.social_media_url  = 'https://twitter.com/ablyrealtime'
   s.documentation_url = "https://www.ably.io/documentation"
-  s.platform          = :ios, '8.0'
+  s.ios.deployment_target = '8.0'
+  s.tvos.deployment_target = '10.0'
+  s.osx.deployment_target = '10.10'
   s.requires_arc      = true
   s.swift_version     = '4.2'
-  s.source_files      = 'Source/**/*.{h,m}'
+  s.source_files      = 'Source/**/*.{h,m,swift}'
   s.private_header_files = 'Source/*+Private.h', 'Source/Private/*.h'
   s.module_map        = 'Source/Ably.modulemap'
   s.dependency 'SocketRocketAblyFork', '0.5.2-ably-2'
   s.dependency 'MsgPackAblyFork', '0.2.0-ably-1'
   s.dependency 'KSCrashAblyFork', '1.15.18-ably-1'
-  s.dependency 'ULID', '1.0.4'
+  s.dependency 'ULID', '1.1.0'
   s.dependency 'SAMKeychain', '1.5.3'
 end
diff --git a/Cartfile b/Cartfile
index de538ec8d..139a57f0e 100644
--- a/Cartfile
+++ b/Cartfile
@@ -1,5 +1,5 @@
 github "ably-forks/SocketRocket" == 0.5.2-ably-2
 github "ably-forks/msgpack-objective-C" == 0.2.0-ably-1
 github "ably-forks/KSCrash" == 1.15.18-ably-1
-github "whitesmith/ulid" == 1.0.4
+github "whitesmith/ulid" == 1.1.0
 github "soffes/SAMKeychain" == 1.5.3
diff --git a/Cartfile.resolved b/Cartfile.resolved
index 8394bb2dd..bd2783158 100644
--- a/Cartfile.resolved
+++ b/Cartfile.resolved
@@ -1,9 +1,9 @@
 github "Quick/Nimble" "v7.3.1"
 github "Quick/Quick" "v1.3.2"
 github "SwiftyJSON/SwiftyJSON" "4.2.0"
-github "ably-forks/KSCrash" "1.15.8-ably-2"
+github "ably-forks/KSCrash" "1.15.18-ably-1"
 github "ably-forks/SocketRocket" "0.5.2-ably-2"
 github "ably-forks/msgpack-objective-C" "0.2.0-ably-1"
 github "soffes/SAMKeychain" "v1.5.3"
 github "whitesmith/Aspects" "1.4.2-ws1"
-github "whitesmith/ulid" "1.0.4"
+github "whitesmith/ulid" "1.1.0"
diff --git a/README.md b/README.md
index b5a46796c..36edde161 100644
--- a/README.md
+++ b/README.md
@@ -12,8 +12,8 @@ An iOS client library for [ably.io](https://www.ably.io), the realtime messaging
 
 This SDK is compatible with projects that target:
 
-- iOS 9.0+
-- tvOS 9.0+
+- iOS 8.0+
+- tvOS 10.0+
 - macOS 10.10+
 
 We maintain compatibility and explicitly support these platform versions, including performing CI testing on all library revisions.
diff --git a/Source/ARTDeviceIdentityTokenDetails.m b/Source/ARTDeviceIdentityTokenDetails.m
index 4cfce4f37..63df5937c 100644
--- a/Source/ARTDeviceIdentityTokenDetails.m
+++ b/Source/ARTDeviceIdentityTokenDetails.m
@@ -86,6 +86,9 @@ - (NSData *)archive {
 }
 
 + (ARTDeviceIdentityTokenDetails *)unarchive:(NSData *)data {
+    if (!data) {
+        return nil;
+    }
     if (@available(macOS 10.13, iOS 11, tvOS 11, *)) {
         NSError *error;
         ARTDeviceIdentityTokenDetails *result = [NSKeyedUnarchiver unarchivedObjectOfClass:[self class] fromData:data error:&error];
diff --git a/Source/ARTPush.h b/Source/ARTPush.h
index d7a870113..b79040786 100644
--- a/Source/ARTPush.h
+++ b/Source/ARTPush.h
@@ -8,10 +8,10 @@
 
 #import <Foundation/Foundation.h>
 #import <Ably/ARTTypes.h>
-#import <Ably/ARTPushAdmin.h>
 
 @class ARTRest;
 @class ARTRealtime;
+@class ARTPushAdmin;
 @class ARTDeviceDetails;
 @class ARTDeviceIdentityTokenDetails;
 
@@ -61,6 +61,7 @@ NS_ASSUME_NONNULL_BEGIN
 
 /// Unregister a device.
 - (void)deactivate;
+
 #endif
 
 @end
diff --git a/Source/ARTPush.m b/Source/ARTPush.m
index e76477c90..c8cf408fb 100644
--- a/Source/ARTPush.m
+++ b/Source/ARTPush.m
@@ -17,6 +17,7 @@
 #if TARGET_OS_IOS
 #import "ARTPushActivationStateMachine.h"
 #endif
+#import "ARTPushAdmin.h"
 #import "ARTPushActivationEvent.h"
 #import "ARTClientOptions+Private.h"
 #import "ARTPushAdmin+Private.h"
@@ -38,7 +39,7 @@ - (instancetype)init:(ARTRest *)rest {
     if (self = [super init]) {
         _rest = rest;
         _logger = [rest logger];
-        _admin = [[ARTPushAdmin alloc] init:rest];
+        _admin = [[ARTPushAdmin alloc] initWithRest:rest];
     }
     return self;
 }
diff --git a/Source/ARTPushActivationEvent.m b/Source/ARTPushActivationEvent.m
index a80ed168e..7760580d7 100644
--- a/Source/ARTPushActivationEvent.m
+++ b/Source/ARTPushActivationEvent.m
@@ -54,6 +54,9 @@ - (NSData *)archive {
 }
 
 + (ARTPushActivationEvent *)unarchive:(NSData *)data {
+    if (!data) {
+        return nil;
+    }
     if (@available(macOS 10.13, iOS 11, tvOS 11, *)) {
         NSError *error;
         ARTPushActivationEvent *result = [NSKeyedUnarchiver unarchivedObjectOfClass:[self class] fromData:data error:&error];
diff --git a/Source/ARTPushActivationState.m b/Source/ARTPushActivationState.m
index 50b0499fc..052efc69c 100644
--- a/Source/ARTPushActivationState.m
+++ b/Source/ARTPushActivationState.m
@@ -77,6 +77,9 @@ - (NSData *)archive {
 }
 
 + (ARTPushActivationState *)unarchive:(NSData *)data {
+    if (!data) {
+        return nil;
+    }
     if (@available(macOS 10.13, iOS 11, tvOS 11, *)) {
         NSError *error;
         ARTPushActivationState *result = [NSKeyedUnarchiver unarchivedObjectOfClass:[self class] fromData:data error:&error];
diff --git a/Source/ARTPushAdmin+Private.h b/Source/ARTPushAdmin+Private.h
index 195f3020f..f8a36aa6d 100644
--- a/Source/ARTPushAdmin+Private.h
+++ b/Source/ARTPushAdmin+Private.h
@@ -6,9 +6,6 @@
 //  Copyright © 2017 Ably. All rights reserved.
 //
 
-#ifndef ARTPushAdmin_Private_h
-#define ARTPushAdmin_Private_h
-
 #import <Ably/ARTPushAdmin.h>
 
 @class ARTRest;
@@ -17,10 +14,8 @@ NS_ASSUME_NONNULL_BEGIN
 
 @interface ARTPushAdmin ()
 
-- (instancetype)init:(ARTRest *)rest;
+- (instancetype)initWithRest:(ARTRest *)rest;
 
 @end
 
 NS_ASSUME_NONNULL_END
-
-#endif /* ARTPushAdmin_Private_h */
diff --git a/Source/ARTPushAdmin.h b/Source/ARTPushAdmin.h
index a9314b26b..6b287e6ee 100644
--- a/Source/ARTPushAdmin.h
+++ b/Source/ARTPushAdmin.h
@@ -21,8 +21,8 @@ NS_ASSUME_NONNULL_BEGIN
 /// Publish a push notification.
 - (void)publish:(ARTPushRecipient *)recipient data:(ARTJsonObject *)data callback:(nullable void (^)(ARTErrorInfo *_Nullable error))callback;
 
-@property (nonatomic, readonly) ARTPushDeviceRegistrations* deviceRegistrations;
-@property (nonatomic, readonly) ARTPushChannelSubscriptions* channelSubscriptions;
+@property (nonatomic, readonly) ARTPushDeviceRegistrations *deviceRegistrations;
+@property (nonatomic, readonly) ARTPushChannelSubscriptions *channelSubscriptions;
 
 @end
 
diff --git a/Source/ARTPushAdmin.m b/Source/ARTPushAdmin.m
index 2f7ef0b19..af4394c6b 100644
--- a/Source/ARTPushAdmin.m
+++ b/Source/ARTPushAdmin.m
@@ -22,12 +22,12 @@ @implementation ARTPushAdmin {
     dispatch_queue_t _queue;
 }
 
-- (instancetype)init:(ARTRest *)rest {
+- (instancetype)initWithRest:(ARTRest *)rest {
     if (self = [super init]) {
         _rest = rest;
         _logger = [rest logger];
-        _deviceRegistrations = [[ARTPushDeviceRegistrations alloc] init:rest];
-        _channelSubscriptions = [[ARTPushChannelSubscriptions alloc] init:rest];
+        _deviceRegistrations = [[ARTPushDeviceRegistrations alloc] initWithRest:rest];
+        _channelSubscriptions = [[ARTPushChannelSubscriptions alloc] initWithRest:rest];
         _userQueue = rest.userQueue;
         _queue = rest.queue;
     }
diff --git a/Source/ARTPushChannelSubscriptions.h b/Source/ARTPushChannelSubscriptions.h
index 9a8680238..4fc351036 100644
--- a/Source/ARTPushChannelSubscriptions.h
+++ b/Source/ARTPushChannelSubscriptions.h
@@ -18,7 +18,7 @@ NS_ASSUME_NONNULL_BEGIN
 @interface ARTPushChannelSubscriptions : NSObject
 
 - (instancetype)init NS_UNAVAILABLE;
-- (instancetype)init:(ARTRest *)rest;
+- (instancetype)initWithRest:(ARTRest *)rest;
 
 - (void)save:(ARTPushChannelSubscription *)channelSubscription callback:(void (^)(ARTErrorInfo *_Nullable))callback;
 
diff --git a/Source/ARTPushChannelSubscriptions.m b/Source/ARTPushChannelSubscriptions.m
index 2e1d763dd..05d439114 100644
--- a/Source/ARTPushChannelSubscriptions.m
+++ b/Source/ARTPushChannelSubscriptions.m
@@ -25,7 +25,7 @@ @implementation ARTPushChannelSubscriptions {
     dispatch_queue_t _userQueue;
 }
 
-- (instancetype)init:(ARTRest *)rest {
+- (instancetype)initWithRest:(ARTRest *)rest {
     if (self = [super init]) {
         _rest = rest;
         _logger = [rest logger];
diff --git a/Source/ARTPushDeviceRegistrations.h b/Source/ARTPushDeviceRegistrations.h
index 61c976cef..977f01a14 100644
--- a/Source/ARTPushDeviceRegistrations.h
+++ b/Source/ARTPushDeviceRegistrations.h
@@ -18,7 +18,7 @@ NS_ASSUME_NONNULL_BEGIN
 @interface ARTPushDeviceRegistrations : NSObject
 
 - (instancetype)init NS_UNAVAILABLE;
-- (instancetype)init:(ARTRest *)rest;
+- (instancetype)initWithRest:(ARTRest *)rest;
 
 - (void)save:(ARTDeviceDetails *)deviceDetails callback:(void (^)(ARTErrorInfo *_Nullable))callback;
 
diff --git a/Source/ARTPushDeviceRegistrations.m b/Source/ARTPushDeviceRegistrations.m
index f94e1b588..f2d6a1a14 100644
--- a/Source/ARTPushDeviceRegistrations.m
+++ b/Source/ARTPushDeviceRegistrations.m
@@ -26,7 +26,7 @@ @implementation ARTPushDeviceRegistrations {
     dispatch_queue_t _userQueue;
 }
 
-- (instancetype)init:(ARTRest *)rest {
+- (instancetype)initWithRest:(ARTRest *)rest {
     if (self = [super init]) {
         _rest = rest;
         _logger = [rest logger];