In Accra's district of Old Fadama, the largest slum in Ghana's capital, a government official interrupts a group of men playing cards. The official carries a tablet and asks if anyone has time for a few questions to test an electronic questionnaire.
Ghana is preparing for its first digital population and housing census next March, joining Swaziland, Malawi and Kenya as one of the first countries in Africa to collect data electronically.
Long-time resident Mohammed Basiru volunteers. He was missed out of the head count during Ghana's previous census in 2010 because he was traveling overnight from the northern city of Tamale.
At that time, questionnaires were on paper. It took months to gather and assemble the data, and around 3% of the population was left out of the survey.
Now the government will be going digital, using tablets and satellite images to improve the reach of enumerators and make sure everyone in Ghana is counted on census night.
Vice President Mahamudu Bawumia said the data would help fight inequality.
"We must count everyone and make everyone accountable to pay their fair share in taxes that would be used to target assistance to those who may not have had access to critical social services previously," said Bawumia at an event last week.
The census is expected to cost $84 million, around 50% more than the last census. The government has contracted around 60,000 enumerators, but is still working with the United Nations on how best to source the 65,000 tablets required to conduct the surveys.
Officials say Kenya may be able to lend out the tablets after it completes its first digital census later this year.
Araba Forson, chief statistician for the Ghana Statistical Service, said technology would prevent enumerators from under-staffing densely populated areas — a problem encountered in 2010 because the population maps they used were out of date.
"Satellite imagery will tell us that there are people living in this part of the country that the enumerator may not have visited," she said. "Using electronic data collection, we will be able to make sure that everyone has been covered."
Ghana's urban population has more than doubled during the past two decades, rising from 7 million in 1997 to almost 16 million in 2017, according to the World Bank.
Many people have moved from poorer rural areas in search for work, joining the millions of street vendors and waste pickers who make up most of Ghana's informal economy.
Together with the homeless, they are the "floating population" whom government statisticians want to capture better in their database.
And the stakes are higher this time, as the census will play a key part in the nationwide rollout of biometric ID cards launched by President Nana Akufo-Addo in 2017. The new Ghana Card requires a digital address code, many of which will be generated by enumerators during the census.
In Agbogbloshie district, notorious for housing a toxic junkyard of electronic waste, community member Naa Ardo-Acquah said some slum dwellers were suspicious of the ID registration process.
"In the Choko community, they thought the card means to tax," she said. "The authorities didn't sensitize them on it."
Ardo-Acqhua hopes the new digital address system will stop city authorities from removing slum dwellers from their homes.
But distrust remains an issue, and officials testing tablets and marking houses in poorer areas said some of their numbers were later removed by informal residents who feared eviction.
"Our publicity and communication team has developed communication materials, both print and audiovisuals, that will be used to educate the people," said Omar Seidu, a social statistician for the Ghana Statistical Service.
Seidu said his team would be working closely with community leaders before the census to make sure the process is understood.
Ardo-Acqhua has said she still worries the government will not send enough staff to Agbogbloshie. She spent days helping people register for their ID cards at centers set up by the National Identification Authority, and said many were discouraged by long lines.
"They only came for three days and less than half the community was able to sign up," she said. "I don't know what they are going to do about that."
