Apple as a company is not responsible for setting foreign policies. Apple is a company, and does what is best for the company. China is where the products are made, they have the largest population in the world (India is closing in very quickly), if they aren't allowed to sell their products in China it will be a big hit for the company.
This is a discussion for US foreign policy/leadership. It is THEIR responsibility to address human rights violations in China, not a private company. If US leadership wants to take a stand and prevent US products from being sold in China due to human rights violations and Apple continues to sell its products then we have room to criticize Apple.
If Apple or it's employees (Tim Cook is an employee), want to take part in parade, or come out against anything that is up to them. If they want to make an app available or unavailable in the app store that is up to them.
If Apples actions led to US citizens getting injured/killed, could you imagine how that would play? We do have US citizens living and working in China. We can't have Apple taking a stand (keeping the app in the store) at the possible expense of US citizens over there.