corebluetooth

These are confidential sessionsplease refrain from streaming, blogging, or taking pictures

Session 703

Core Bluetooth

Jason ConnCode Monkey & Radio Sponge

Brian TuckerBluetooth SIG Grand Wizard

Renaud LienhartKeeper of the Code & General Curmudgeon

BLE State of the Union

Evolution of Core Bluetooth

Core Bluetooth in iOS 7

Code Demo

Tips and Best Practices

BLE: State of the Union

Brian TuckerBluetooth SIG Grand Wizard

Source ABI Research 2013

Projected BLE Accessories Shipped1 Billion+

Projected BLE Accessories Shipped

0

750

1,500

2,250

3,000

2012 2013 2014 2015 2016 2017 2018

Source ABI Research 2013

1,009,000,000 Devices

Proximity

Security

Automation

Health Care Sports/Fitness

Entertainment Toys

Pay Systems Time Services

Evolution of Core Bluetooth


Observer, Central, Client

CBCentralManager Discover peripherals Connect

CBPeripheral Access remote services

iOS 5

Broadcaster, Peripheral, ServeriOS 6

CBPeripheralManager Host services Advertise information Field CBCentral requests

Peripheral database caching

LE, EvolvedCore Bluetooth in iOS 7.0

Ch-ch-ch-changes

Simpler device management Smarter peripherals Performance improvementsApplication persistence Built-in services

Whats New

That is the questionTo Simulate, or Not to Simulate

Emerging market Limited hardware available

No iOS devices

Development difficult


Exploding marketMany LE-compatible devices

All iOS hardware Macbook, Mac mini

Third-party development kits


Exploding marketMany LE-compatible devices

All iOS hardware Most Mac hardware

Third-party development kits

Handling centrals and peripheralsSimpler Device Management

Bye, bye CoreFoundation


@property(readonly, nonatomic) CFUUIDRef *UUID;




@property(readonly, nonatomic) NSUUID *identifier;




@property(readonly, nonatomic) NSUUID *identifier;

Identifiers created at discovery

Retrieving peripherals, todaySimpler Device Management

CBCentralManager


retrievePeripherals:

CBCentralManager


didRetrievePeripherals:


CBCentralManager




CBCentralManager

retrieveConnectedPeripherals




CBCentralManager

retrieveConnectedPeripherals

didRetrieveConnectedPeripherals:

Retrieving peripheralsSimpler Device Management

CBCentralManager


retrievePeripheralsWithIdentifiers:

CBCentralManager



CBCentralManager



CBCentralManager


, the iOS 7 way


CBCentralManager


retrieveConnectedPeripheralsWithServices:

, the iOS 7 way


CBCentralManager


retrieveConnectedPeripheralsWithServices:

connectPeripheral:options:

, the iOS 7 way

Smarter Peripherals

Smarter Peripherals

More connection-aware@property(readonly) BOOL isConnected;

typedef NS_ENUM(NSInteger, CBPeripheralState) { CBPeripheralStateDisconnected = 0, CBPeripheralStateConnecting, CBPeripheralStateConnected };

@property(readonly) CBPeripheralState state;

Smarter Peripherals

Smarter Peripherals

Better service invalidation

Smarter Peripherals

Better service invalidation(void)peripheralDidInvalidateServices:(CBPeripheral *)

Smarter Peripherals

Better service invalidation(void)peripheralDidInvalidateServices:(CBPeripheral *)

(void)peripheral:(CBPeripheral *)didModifyServices:(NSArray *)

LE, EvolvedCore Bluetooth in iOS 7.0


Performance Improvements

ServiceHeart Rate Monitor

CharacteristicHeart Rate Measurement

Database caching, todayPerformance Improvements





Characteristic Value190

DescriptorClient Configuration


Introduced in iOS 6 ServiceHeart Rate Monitor







Introduced in iOS 6 Increases speed and battery life








Introduced in iOS 6 Increases speed and battery life Cache services and characteristics







Database caching, in iOS 7Performance Improvements









Cache characteristic descriptors










Cache characteristic descriptors Caching for characteristic values?











Provide last-known characteristic values and descriptor values












Provide last-known characteristic values and descriptor values

Free!











Sending dataPerformance Improvements

115 BPM


115 BPM


Mon Tues Weds Thurs

58

70

43

55

96

53

26

17

Mon Tues Weds Thurs

50%

28%

14%9%


Support MTU exchange request


Support MTU exchange requestMaximum amount of data per PDU


Support MTU exchange requestMaximum amount of data per PDU Send more data at a time

Sending data

Default MTU23 bytes


Sending data

Default MTU23 bytes

Increased MTU??? bytes



When central, ask for larger MTU


When central, ask for larger MTUUp to 20% increase in throughput


When central, ask for larger MTUUp to 20% increase in throughput Free!

Performing long-term actionsPerformance Improvements

Living in a multitasking worldPerforming Long-Term Actions


Backgrounding modes


Backgrounding modes App communicates using CoreBluetooth


Backgrounding modes App communicates using CoreBluetooth App shares data using CoreBluetooth



Background applications can be terminated by system



Background applications can be terminated by system Some use-cases take hours

Our solutionPerforming Long-term Actions


System watches application state


System watches application stateWhen application is terminated



If cause is memory pressure



If cause is memory pressure If application is performing long-term action(s)




System acts as application proxy




System acts as application proxyWhen needed, application is re-launched

State Preservation and Restoration


Opt-in


Opt-in Supported by CBCentralManager and CBPeripheralManager


Opt-in Supported by CBCentralManager and CBPeripheralManagerMinimal implementation

Provide unique identifier for manager Implement new delegate method

A picture is worth a thousand wordsState Preservation and Restoration


Snapshot taken before termination


Snapshot taken before termination CBCentralManager



Scanning state



Scanning state Pending/active connections



Scanning state Pending/active connections Peripheral subscriptions




CBPeripheralManager




CBPeripheralManager Advertising state




CBPeripheralManager Advertising state Published services




CBPeripheralManager Advertising state Published services Central subscriptions

Back from the deadState Preservation and Restoration


Events that system cant handle trigger application re-launch


Events that system cant handle trigger application re-launch Peripheral connects, central subscribes, notification received, etc.



Application re-launched into background, running



Application re-launched into background, running Re-instantiates appropriate manager object(s)



Application re-launched into background, running Re-instantiates appropriate manager object(s) Delegate callback provides all preserved state



Application re-launched into background, running Re-instantiates appropriate manager object(s) Delegate callback provides all preserved state Power on event



Application re-launched into background, running Re-instantiates appropriate manager object(s) Delegate callback provides all preserved state Power on event Delegate callback for triggering event

DemoAdding State Preservation and Restoration Support


Bluetooth Low Energy graduatesBuilt-in Services


GATT ClientBuilt-in Services


HID Over GATT Profile HID, Battery, Device Information services


HID Over GATT Profile HID, Battery, Device Information services

Works just like Bluetooth Classic Managed from Bluetooth Settings iOS automatically reconnects paired peripherals

GATT ServerBuilt-in Services


Battery Service


Battery Service Current Time Service

Accurate time and date Time zone information


Battery Service Current Time Service

Accurate time and date Time zone information

One more thing

Notificationsthe problemsBuilt-in Services


Message Access Profile (MAP)


Message Access Profile (MAP) Developed for an automotive usage


Message Access Profile (MAP) Developed for an automotive usage Very constrained: SMS, MMS, Email



Alert Notification Service



Alert Notification Service Very limited




Custom app tailored to a specific accessory




Custom app tailored to a specific accessory Heavyweight




Custom app tailored to a specific accessory Heavyweight Data limited to what the sandbox allows

Notificationsour solutionBuilt-in Services


Apple Notification Center Service


Apple Notification Center Service Apple-specific


Apple Notification Center Service Apple-specific Notification about any events on your phone



Incoming and Missed calls, Voicemails



Incoming and Missed calls, Voicemails Instant messages, Emails



Incoming and Missed calls, Voicemails Instant messages, Emails Calendar alerts



Incoming and Missed calls, Voicemails Instant messages, Emails Calendar alerts App notifications




System automatically reconnects




System automatically reconnects Detailed specification posted on the developer portal soon

Apple Notification Center ServiceBuilt-in Services

New iMessage

New iMessageNew Social Notification, UID=1


GetAttributes(UID=1,Title,Msg)



Title=Jason,Msg=Beers?




Alert User




iMessage Read

Alert User




iMessage Read Notification Removed, UID=1

Alert User




iMessage Read Notification Removed, UID=1

Alert User

Dismiss Alert


Core Bluetooth needs to know if you intend to use CBPeripheralskeep a reference to them


Core Bluetooth needs to know if you intend to use CBPeripheralskeep a reference to them Scanning and connection requests do not time out


Core Bluetooth needs to know if you intend to use CBPeripheralskeep a reference to them Scanning and connection requests do not time out CBPeripheral and CBCentral conform to NSCopying and can be used as dictionary keys


Core Bluetooth needs to know if you intend to use CBPeripheralskeep a reference to them Scanning and connection requests do not time out CBPeripheral and CBCentral conform to NSCopying and can be used as dictionary keysDo not touch Client Configuration Characteristic Descriptors directly


Core Bluetooth needs to know if you intend to use CBPeripheralskeep a reference to them Scanning and connection requests do not time out CBPeripheral and CBCentral conform to NSCopying and can be used as dictionary keysDo not touch Client Configuration Characteristic Descriptors directlyDo not game the background mechanisms

Bluetooth best practices

http://developer.apple.com/hardwaredrivers/BluetoothDesignGuidelines.pdf

Apple Guidelines

Core Bluetooth Programming Guide

Finally!

Apple Guidelines

Craig KeithleyMFi & I/O Technology [email protected]

Stephen ChickiPhone [email protected]

Developer ProgramsMFi Programhttp://developer.apple.com/mfi/

More Information

Bluetooth Accessory Design Guidelineshttp://developer.apple.com/hardwaredrivers/BluetoothDesignGuidelines.pdf

Reporting Bugshttp://bugreport.apple.com

Apple Developer Forumshttps://devforums.apple.com/community/ios/core/cbthttps://devforums.apple.com/community/mac/coreos/cbt

Bluetooth Developer Sitehttp://developer.bluetooth.org

More Information

Whats New in Core Location PresidioThursday 11:30AM

Related Sessions

Designing Accessories for iOS and OS X Nob HillTuesday 10:15AM

Labs

iOS and OS X Accessories Lab Core OS Lab BThursday 9:00AM

iOS and OS X Accessories Lab Core OS Lab ATuesday 11:30AM

ProximitySecurityAutomationHealth CareSports/FitnessEntertainmentToysPay Systems

Proximity

Security

Automation


Entertainment

Toys

Pay Systems

Proximity

Security

Automation


Entertainment

Toys

Pay Systems

Connect the World

corebluetooth

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