Phân tích dự án ứng dụng nhắn tin miễn phí Zalo, quá trình phát triển ứng dụng và users tại việt namx

Inside Zalo: Developing a mobile messenger for the
audience of millions
BY THANH DAO, VNG CORP.


About me
Career:
• VNG: Senior Manager - Head of Zalo & Zing
Mobile Product Group
• Past: Microsoft, Kofax

Contact:
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My Goals
• Talk about how we started a mobile first
product, growing the user base and the
learned lessons that lead us here.
• Give you a blueprint for how to scale your
mobile server system to millions.


Agenda
• Background of Zalo
• The user growth story
• Continuous development


Landscape before Zalo
Social Networks

Sticky, but...
• Don’t support mobile first
use-case and phonebook
graph.
• Not focus on enhance chat
and group chat
• My mom, sister don’t
contact me via SNS

Traditional Messengers

Strong network effect on PC,
but...
• No social features
• Not fun enough
• Not mobile friendly

OTT IM

Early movers & viral, but…
• No profile, social features.
• Lack of fun features appeal
to the young users
• Can’t customize a feature
for the Vietnamese
5community
• Low barrier to entry

Model of Zalo
Mobile social messaging:
• Based on Mobile First & Phonebook Graph
• Combine Context Messaging & Connecting &
Circle Socializing
• Viral (i.e SMS/Zing/Facebook…)
• Sticky
• Mass market appeal


Target
18-25

26-30

Singles

Core segment

Core segment

Unmarried
couples

Potential to grow share

?

Married
couples

Potential to penetrate

X

X

Not target yet

Not target yet


Product

Platform
Product

1. Communication: Voice messaging & Call…
2. Social: Timeline, People Near By, Room…
3. Platform: Page, 3rd Apps, Games.

Proposition(Value)

“Fun & Connection & Private”
Anchored by basic: Fast, Quality, Cheap

P lace (Channel)

1. App Stores: Itunes, Google Play, Nokia Store
2. Factory Preload on Nokia Asha, WP…

3. Side-load at retail shop


Marketing
• Position as an Expression/Lifestyle.
• Focus on messaging the brand benefit
– “Talk more to your loved ones”

•360 Campaign launch at Online, Social, PR, TVC, OOH (Cinema, University,…)


Agenda
• Background of Zalo
• The user growth story
• Continuous development


Agenda
• Background of Zalo
• The user growth story
• Continuous development


User Discovery Q3/2012: Born
Product

25000000

• Zing & Phonebook mobile messenger
• voice, sticker, draw and people near by

20000000

Users feedback and data told us

So we
• Removed “Chat with Zing friends” feature
and focused on the Mobile First use-cases
• Rewrote our own socket chat servers instead
of relaying via Zing Me Web Chat servers

15000000

10000000

5000000

0
5/
1
4/ 2/2
2 0
4/ 8/2 13
1 0
3/ 4/2 13
3 0
3/ 1/2 13
17 01
3/ /20 3
2/ 3/2 13
17 01

2/ /20 3
1/ 3/2 13
20 01
1/ /20 3
12 6 / 1 3
/2 20
12 3/2 13
11 /9/ 012
/ 2
11 2 5 / 0 1 2
/ 2
10 1 1 / 0 1 2
/ 2
10 2 8 / 0 1 2
/1 20
9/ 4/2 12
3 0
9/ 0/2 12
16 0 1
9/ /20 2
8/ 2/2 12
1 9 01
/2 2
01
2

• Good for dating purpose
• The draw & games, sticker are fun
• The concept of mixing up Zing & phonebook
graph is confusing, they want a separated

buddy list
• Sending speed is slow with 3G, drain the
battery lifecycle
• Nokia version is not available yet

Registered User

Daily msg


User Discovery Q4/2012: Totter
Product
New version Nokia/Droid/IOS
Group, Room
Social Timeline

Users feedback and data told us
•
•
•
•

Voice/text is fast
UX is much better than the prev one
Spam and privacy concerns
Not enough friends so both retention and
engagement are problems

15000000

10000000

5000000

So we
•
•
•

20000000

Improve notification services
Improve picture quality
Scale up advertising budget, Run 360 degree
marketing campaign

0
5/
1
4/ 2/2
2 0
4/ 8/2 13
1 0
3/ 4/2 13
3 0
3/ 1/2 13
17 01
3/ /20 3
2/ 3/2 13
17 01

2/ /20 3
1/ 3/2 13
20 01
1/ /20 3
12 6 / 1 3
/2 20
12 3/2 13
11 /9/ 012
/ 2
11 2 5 / 0 1 2
/ 2
10 1 1 / 0 1 2
/ 2
10 2 8 / 0 1 2
/1 20
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3 0
9/ 0/2 12
16 0 1
9/ /20 2
8/ 2/2 12
1 9 01
/2 2
01
2

•
•
•

25000000

Registered User

Daily msg


User Discovery Q1/2013: Walk
Product
•
•
•
•

Friend Circle
Zalo Page (VIP)
Friend invitation
Support 18 countries

Users feedback and data told us

25000000

20000000

15000000

• Voice message is addictive
• Multi-picture upload is convenient
10000000

So we
5000000

0
5/
1
4/ 2/2
2 0
4/ 8/2 13
1 0
3/ 4/2 13
3 0
3/ 1/2 13
17 01
3/ /20 3
2/ 3/2 13
17 01
2/ /20 3
1/ 3/2 13
20 01
1/ /20 3
12 6 / 1 3
/2 20
12 3/2 13
11 /9/ 012
/ 2
11 2 5 / 0 1 2
/ 2
10 1 1 / 0 1 2

/ 2
10 2 8 / 0 1 2
/1 20
9/ 4/2 12
3 0
9/ 0/2 12
16 0 1
9/ /20 2
8/ 2/2 12
1 9 01
/2 2
01
2

• Run Friend Invite Campaign
• Developing Call.
• Work with 3RD party apps

Registered User

Daily msg


Agenda
• Background of Zalo
• The user growth story
• Continuous development


Stats

• 2.3M registered users (40% Droid; 30% IOS;
30% Nokia).
• >500K new users join a month.
• 800K DAU
• 380K peak CCU
• 20M messages sent a day.
• 39 servers, 150M requests a day.


Server Platform
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CentOS
Binary protocol, SSL, TCP/IP, UDP.
C++ for core, java for other business services.
Za-Router, long connection service map and load balancer.
Za-DB: a key-value db storage similar to Amazon Dynamo/Google Big T.
Za-Cache: memory caching system.
Za-Session manager
Za-CDN
Za-Messaging/Signal Socket Server
Za-Stream Download/Upload Server.
Za-Voice/Video Media Proxy Server
Za-Configuration center: synchronize config among services.
Za-Monitor center + zabbix + nagios + cacti + dogslow: trend monitoring.
Postgre SQL(PostGis): store lbs data, can handle >10k requests/sec with memory caching.
Dynamic DNS
HA Proxy: web load balancer(https login services).
Squid: static content caching, small photo…
Hadoop: data analyzing and mining
Elastic search
Scribe for log, backup…


ZA Socket Protocol

Monitoring

ZAComm Router

ZAComm

ZAComm #1
#1

ZAComm
ZAComm #2
#2

ZAComm
ZAComm #N
#N

Conn
Conn Manager
Manager

Conn Manager

Conn
Conn Manager
Manager

Worker Pool

Worker
Worker Pool
Pool

Worker Pool

Worker

Worker

Worker

Worker

VIP

Msg

Avatar

Contact

LBS
LBS

Group
Group

Photo
Photo

Privacy
Privacy

Room
Room

Share

Cover
Cover

Friend
Friend

LBS
LBS

Message
Message Items
Items

Photo
Photo

Caching
Caching

Caching

Caching
Caching

Persistent

Persistent

Persistent

MemCache

Background Job


Server Infrastructure
39 Servers:
• 6 relay storage servers
• 9 database servers
• 6 business application servers
• 3 proxy caching servers
• 4 other caching servers
• 4 backup servers
• 3 log and monitor/configuration servers

Capacity:
•
•

1M CCU
I/O speed: 200K message/sec


Scalable Mobile Servers
• Scaling connection servers
– Each connection server handle a shard of users.
– Configuration center.
– Service map.

• Scaling database
– Distributed hash table design.
– Backup & recovery.
– No alter on large table, create new one.
– Soft deletion, Lazy write.

• N+1 design
– Build horizontally, never less than two of anything.
– No single point of failure.

• Think about monitor during design, not after.
• Identify where bottlenecks are in each tier
– Control Port(CPU).
– Data Port(Network/Memory/Cache/Storage IO…).