A talk I gave on iBeacons and Eddystone at the London Xamarin user group on 26th August 2015

1. Building context aware
apps with iBeacons and
Eddystone
Jim Bennett
@JimBobBennett
http://JimBobBennett.io

2. Overview
• A quick overview of beacon technology
• What are context aware apps?
• What is iBeacon?
• What is Eddystone?
• Demos

3. What are beacons
• Bluetooth LE devices
• Broadcast a signal at a defined interval with a
defined data packet
• They don’t rely on a client connection, just a
regular, public broadcast
• Low power - some run off USB, some run of
batteries with lifetimes in months to years

4. What are context aware
apps?• Context aware apps are aware of some kind of
contextual information provided by the devices
location relative to the beacons
• Better than GPS as this can work indoor as well as
out
• Context is based off the location of a beacon, and this
is not necessarily a fixed point
• Context is defined by an multi part id
• Beacons broadcast a signal strength indicator so the
device can get an approximate distance based off
the received signal strength

5. What apps can you build
to take advantage of
this?• Museum guide - app knows which exhibit you are
standing next to and plays the correct audio
• Stadium location - app can pinpoint your location
and direct you to your seat, and let you know when
a beer seller is close by
• Shopping - notifications of special offers when you
are next to the items on offer
• Respond to indoor location - turn your lights off
when you put your phone down on your bedside
table, notify friends when you are home safe

6. Problems!
• Security - anyone can read your beacon by
scanning for Bluetooth devices and spoof your
id
• Power - some beacons run off the mains so
need socket, battery powered ones will die
and need replacing
• Accuracy - not very, for example in a busy
location people can decrease signal strength

7. What are iBeacons?
• Apple’s beacon specification
• Message has an Id, version
(major, minor), measured
power
• Multiple iBeacons can have
the same Id, versions can be
used to distinguish different
iBeacons

8. How do they interact with
your iOS app?• Apple defines an API to interact
with iBeacons as part of
CoreLocation
• Apps can register to monitor a
region - all beacons with a given
Id
• Monitoring notifies when an
iBeacon moves in or out of
range
• Monitoring can happen in the
background even if your app is
terminated and will launch your
app
• Once your app is in the
foreground, you can range the
iBeacons to get their
proximity/distance as it changes

9. What is Eddystone?
• Google’s beacon specification - recently
announced and open source
• Broadcasts one of two possible message
formats
• Eddystone UID broadcasts a UID and a
version
• Eddystone URL broadcasts a URL (limited
length)
• Eddystone TLM goes alongside one of the
other 2 formats and provides telemetry
• Beacon broadcasts can wake your Android
app up

10. Which one is better?
• Eddystone URL allows discovery - can be detected
by Chrome instead of a custom app
• Downside is spamming with too many URLs
• Apple provides OS level interaction with iBeacons so
can wake your iOS app up - iBeacons can work on
Android with manufacturers SDKs but can’t wake
your app up
• Eddystone can interact with the latest Google Play
services and wake your Android app up, but not an
iOS app
• In the future beacons could broadcast multiple
packets to wake apps up on both platforms

11. Using beacons with
Xamarin
• iBeacons on iOS is available in CoreLocation
• Eddystone on Android is available in Google
Play Services 7.8
• Google is releasing a Nearby API for iOS and
Android that supports Eddystone on both
platforms - no Xamarin binding yet
• Estimote (a beacon vendor) has a Xamarin
component for iOS and Android that supports
iBeacon, needs to be updated to support
Eddystone

12. Demo time!