In front of our camera, a group of around 20 women are limbering up.
“She’s 71,” one of the class proudly told us, pointing out a beaming woman in immaculate black and pink robes.
Most of the women are grandmothers, but this was no sedate morning stretch.
Some of the group demonstrated headstands and splits, as the others clapped and cheered them on.
But the day’s main challenge would require different skills.
In between rounds of Tai Chi, an ancient Chinese martial art, the ladies had come to learn about smartphones, and mastering social media.
China has changed dramatically from the country these ladies grew up in – it is now the world’s biggest smartphone market.
More than half the population is online.
So they’re taking part in a six-week community course to get up to speed.
The first task: joining the Wi-Fi.
The teacher held up her phone, in its bright yellow foam “minion” cover, and talked them through the process.
Two pink-suited assistants spread out, correcting passwords, and urging those who had already connected, not to disconnect.
The women are taught how to use WeChat, a popular Chinese social-messaging app, as well as how to order taxis and pay utility bills online.
Online shopping seemed to be very popular.
One of the group showed us the brightly coloured dance outfits she had ordered, and the fashion snaps she sends to her daughter.
But the real hit is video calls.
The class divided into smaller groups to practice: shouting and laughing into the mobile phone screen at their partners, in real life, sitting just metres away.
Wie Jingzhen, at 55 the youngest member of the group, talked us through the benefits.
“Say I want to get in touch with big sister over there,” she explained, “to see whether she is going to Tai Chi, I just get out WeChat and make a video call with her.
“I don’t have to go round there in person so I save a lot of time.”
She said it was much better than just talking on the phone.
“As soon as I see her, I feel really happy – It feels like we’re much closer together, as though we’re in front of each other,” she continued.
“This is like I’m seeing her for real.”
Fu Yuanxiu, 63, showed us a video she had edited of her morning exercise routine, complete with music and animated birds.
The only problem now – she is slightly addicted.
“As soon as I wake up, I look at my phone to see what is happening, what news there is, I can’t ever be without my phone now,” she said.
“If my phone ever runs out of battery that would make me really nervous now.”
“Their emotional life can be empty after they retire,” said class organiser, Shi Yaru.
“They can use the cellphone to find new activities for their lives, to bring many people together, so they do not feel lonely.”
Lu Shulian, 71, said the class had helped them make new friends, both on and offline.
“We’re coming out to exercise together, but we’re also getting to socialise and arrange things,” she said.
“We go travelling together, we go dancing together, so all the good things in life we can share.”
After a break for some Tai Chi – to stretch out those shoulders, and shake off all that smartphone stress – two of the star pupils gave us a masterclass in the art of the video call.
“Hi, how are you? I really miss you!” Ms Wie bellowed at the screen, holding up two fingers in the v-sign that is fashionable here. “Can you see me or not?”
“Yes, I can see you,” Ms Fu yelled back, from two metres away.
“You look really beautiful.
“Are you going to Tai Chi today? Have you been studying the new moves?
“Yes, I’m going as well.”
Business concluded, the women waved goodbye to each other, promising to chat again soon, before dissolving into fits of giggles, to a round of applause from the rest of the class.