Some users reported that the only way to use the app properly was through tools that circumvent the country's strict internet blocks, dubbed the Great Firewall.
The problems have led users to speculate that the Chinese Government could have partially blocked WhatsApp, which offers users more privacy from spying authorities than alternative apps because it uses end-to-end encryption.
It comes after reports earlier this week that Chinese authorities were intercepting and deleting WeChat messages commemorating Liu Xiaobo, the Nobel Laureate who died after years of imprisonment in the country.
Citizen Lab, a monitoring project at the University of Toronto, said images related to Xiaobo were blocked in private messages, group chats and on WeChat's Moments feed following his death.
"Chinese social media companies receive greater government pressure around critical or sensitive events," said Citizen Lab. "Our findings document a significant shift in censorship after Liu Xiaobo's death."
China also appears to have blocked all results on Xiaobo from the Weibo search engine.
More about: #WhatssApp #China
