OA products will have their own IM and instant messaging platforms. Although not as powerful as QQ, it can meet the basic communication.
And OA has more about process management. For example, your company has a business trip approval process. You can use OA system to build a business trip approval process exactly the same as the reality: business trip applicants only need to fill in the information such as business trip time and flight on the form, and then submit it to their own leaders for approval. After you come back from a business trip, you can print the business trip approval form and submit it to the financial reimbursement. How easy it is. This kind is incomparable to QQ.