Apple has sent out press invitations to its 2019 fall event which will take place at Apple headquarters on September 10. This is the exact date that many rumors sites predicted.
This mid-September event usually is where Apple announces new iPhones. This year Apple is rumored to be coming out two new top-level OLED phones with a triple-camera setup and a new base model LCD phone with a dual camera. There should be new processors and some new features such as improved Face ID, durability and battery improvements.
Apple will either release or announce imminent release dates for iOS 13 and macOS Catalina. There may also be new Apple Watch models, perhaps with new materials such as titanium and ceramic. There are also rumors of a new 10.2-inch iPad, and new iPad Pro models, in addition to a new 16-inch MacBook Pro. But it is possible that these may appear at a later announcement or not at all.