A man has vented his frustration online after he came across a new bathroom trend on a visit to San Francisco in the US.
Novelist and journalist Tim Maughan said on Saturday during his "first day proper in San Francisco" he needed to use a bathroom at a cafe and was prompted by staff to install an app on his phone.
Maughan shared an image from the bathroom on Twitter, showing a QR code scanner that unlocked the bathroom door.
"Refused to install app so server printed me out a single use QR code," he said. "How do you people accept living like this."
His post has attracted more than 10,000 likes and 2100 retweets and prompted hundreds of replies.
"What the hell is this," one shocked commenter asked.
"You need an app to pee now. This is 2020," one incredulous person said.
"What if you don't have a phone," another wondered.
"Silicon Valley: We have an app for that. Even when we really, really shouldn't," another joked.
"I shudder think how Good2Go is using the data collected and to whom they are selling it," one person said in response to the photo.
Other Twitter users said the smart bathroom technology had been rolled out in other parts of the world.
This included examples in China, where people at a public restroom in a mall in Chengdu were forced to scan their WeChat codes if they wanted toilet paper.