The operators of smartphone applications will be deemed to have illegally collected or misused personal information if they fail to inform users why they need to collect such information and how it will be used, a guideline released by the authorities on Monday said.

The Cyberspace Administration of China, the Ministry of Public Security, the Ministry of Industry and Information Technology and the State Administration for Market Regulation issued the guideline, which clarifies the behavior required of app operators when they collect personal information.

The guideline, a move to implement the Cybersecurity Law that came into effect in 2017, will help law enforcement departments detect and fight privacy-related violations, the authorities said.

Under Chinese laws and regulations, personal information mainly deals with a person's identity or private activities, and can include their name, identity card number, telephone numbers, and details of their properties or their whereabouts.

The guideline orders app operators to have clear rules on collecting or using personal information, which must be disclosed when users open an app for the first time.

As well as being required to specify what private information of users will be collected, app operators must also inform users why and how they collect or use the information, especially when the information is sensitive-such as identification card and bank account numbers.

App operators who mislead users to get their permission, or intentionally hide or cover up their aims in collecting or using the private information of users, will be deemed to have illegally collected or misused it.

In January, the four authorities launched a campaign against the illegal collection or use of personal information and ordered law enforcement departments to crack down on such behavior. Monday's guideline will help them identify such misconduct.

Li Ya, a Beijing lawyer from Zhongwen Law Firm, welcomed the guideline.

"Detailing the illegal behaviors is crucial for app enterprises to regulate their behaviors when running their businesses and also helpful for users to distinguish whether the app companies are infringing their privacy or not," he said.

The guideline, effective from Monday, will help the authorities supervise the app market and prevent excessive collection or use of private information by operators, he added.

Xu Hao, another Beijing lawyer from Jingsh Law Firm, said, "Users are the ones with the right to decide whether their private information can be used or collected, so the requirement that app companies should offer clear rules on collection or usage to ensure users can understand the rules is, I think, a must."

As legislators draft the country's first law on personal information protection, Xu said the practical guideline will better fight illegal behavior and help maintain market order.