Billy OderoBrian OmwengaMokeira Masita-MwangiPauline GithinjiJonathan Ledlie

Tangaza: Results from Kenya Pilot

Talk OutlineTangaza

• Motivation• Design• Pilot Results• Conclusions

Optimizing Markets via Mobile Phones

Fishing in Indian State of Kerala [Jensen07]

• Coverage grew from nothing to 100% from 1997 to 2000

• Market efficiencies• Knew where to take fish for good price• Price fluctuations cut• Less waste

Kenyan Agricultural Commodity Exchange• Nationwide prices available via text

message subscription• No need to trust middleman

(who farmer is selling to!)• Goods now sell closer to market rates

MotivationFishing & Commodities

Examples of one-to-one communication

What if: Group Communication?• Like Twitter, Yahoo groups, etc.• Constraints

• Cheap to use; cheap to run• Large audience: existing hardware (S30 phones)

o SMS, Speech/calls, USSD

• Enable economic and social benefit?

Why not wait?Could we not deploy a group communication tool for

the web?

For large-scale use, must be available for basic GSM phones• Could connect with web/advanced phone based service

Few advanced devices by 2013

Source: Pyramid Research

Solution: Tangaza (“announce”)

Enable group communication with basic phones• Server-side; no client software• SMS commands; primarily spoken messages (“tangazos”)

Create A send: create testgroup 2

A recv: OK. Created the public group testgroup, assigned key 2

Join A send: invite testgroup 07222981234 0719115678

B, C recv: A invited you to the testgroup group. Reply join testgroup

B, C send: join testgroup

A recv: A new user B<0722981234> has joined testgroup

Text A send: @testgroup Meeting is at 6pm tomorrow

B, C recv: Meeting is at 6pm tomorrow A@testgroup

Tangazo B calls: Selects key 2, Records: Hi, was great to see you both!

A, C flashed: Each observes existence of new tangazo

A, C call: Each listens to B’s message

Talk OutlineTangaza

• Motivation• Design• Pilot Results• Conclusions

Design FeaturesSimple IVR

• Shallow, few options• DTMF-only

• Speech recognition: errors, multiple languages• Faster and cheaper

• Prompts in Swahili and English (saved)• Short tangazos only

SMS Commands• Few required for basic operator• Assume tech savvy people run larger groups

Privacy and Access Restrictions• Public and private groups• Nicknames, not phone numbers

Call User Interface (IVR)22 sec to leave 20 sec tangazo

Talk OutlineTangaza

• Motivation• Design• Pilot

• Two Deployments• Methodology• Results

• Conclusions

Two Kenya Deployments

Huruma Slum (“Slumcode”) Strathmore University

Income:Participants:Occupations:Phone Usage:

low13part-time; unemployedshort, frequent calls

medium-high87Studentsmore texts and minutes overall

Did income and pre-existing mobile phone usage affect Tangaza user behavior?

Methodology

Three month trial 1H10• Unlimited free use• SMS reimbursements, callbacks• Slumcode paid

System Logs• Strathmore: 87 active / 440 total• Slumcode: 13 active users

Surveys• 11 Slumcode; 19 Strathmore

Interviews• 12 Slumcode users• Had used for six days• Integrated feedback

Group lead

Most active

participant

Usage Patterns Slumcode more active

• 65% more calls, 80% more texts per person• Maximized tangazo length

Group Types• Physical: “slumcode,” classes, homework, club, church

Contents• Texts: mainly used for greeting• Tangazos

• Homework assignment• Coordinating events (Swahili)• Well-wishing (Valentines)

Hi people, this is Jamo. dont forget to show up for the valentines snack party at mtoto palace. And dont forget to tangaza back

User FeedbackUser Interface

• “somewhat easy”• Invalid group names: “odhoji’s”• Most preferred short tangazos

Privacy• Many unaware of nickname feature• Did not like phone number disclosure

Notifications• Some: “spam,” “irritable by flashing you at odd times”• Others: liked reminders; fast: “flash of time”

Grandmother-mode• Simpler UI for “upcountry grandmother”?

Cost consistency• Slow crediting: frustration and distrust

Tangaza: Conclusions“Frugal” group communication

• Existing (legacy) phones• Link with advanced phones?

Feedback• Generally positive• Implementable suggestions

Potential• Its own service; part of advanced one• Integrated into other more targeted services

Extra Slides Follow

System Architecture