Politicians, clerics, feminists and others have formed a broad coalition of Ugandans calling Tuesday for an end to a social media tax the government hopes will raise revenue and silence "gossip".
On Sunday Uganda's communications regulator blocked access to social media including WhatsApp, Facebook and Twitter, as well as dating sites Tinder and Grindr, unless users pay a Shs200 ($0.05, 0.04 euro) daily tax.
The outcry was immediate.
"I was in a village on Sunday when the tax started and people were outraged," said Siraje Nsambu, a spokesman for the Tabliq Muslim sect.
"Even a poor boy will [now have to] strive hard to buy a Chinese mobile phone and get online." he said.
Feminist writer and activist Edna Ninsiima slammed the "insane" tax.
"It's trampling freedom of expression and infringing our rights," she said.
Mobile internet users now have to input a telephone code to pay the tax before they are able to access most social media sites, although implementation has proved patchy with some blocked services still available.
Some have turned to virtual private networks (VPNs) to disguise their location and avoid the levy, a trick learned during elections two years ago when the government tried to shut down social media.
Finance minister David Bahati said Tuesday the tax will help pay for "the development of the country" and ordered the communications regulator to stop Ugandans using VPNs, though it is unclear how this directive can be carried out.
President Yoweri Museveni, an avid Twitter user with 855,000 followers, urged the imposition of the tax earlier this year, to put an end to "gossip".
Opponents have given these justifications short shrift.
"The whole idea of the tax is to curtail social media," said singer and parliamentarian Bobi Wine, real name Robert Kyagulanyi, whose election last year was fuelled by social media and who wants the tax abolished.
"The mood is crazy, people are angry!" he said.
"This is not political anymore, it's a social problem and the people are asking for answers."
Business people have been angered too, not least by an associated tax, also imposed at the weekend that charges one percent on every moble money transaction, a popular way to take payments and distribute salaries.
"My business works on mobile money," said Hannington Bugindo, who runs rents out excavators and construction equipment.
Dozens of the tax protesters, describing themselves as "the young citizens of Uganda", warned in a statement Tuesday that unless the levy is lifted by noon Friday they will "mobilise the country" against it.