Apple may be obliged to delay its adoption of 5G until 2020 at the earliest. This is due to its ongoing feud with Qualcomm, who, as it is claimed, will not sell the necessary hardware to the Cupertino company. More recently, Huawei has said it may sell its own modems to Apple.
https://www.notebookcheck.net/Apple-may-have-a-new-prospect-for-5G-modems-Huawei.416089.0.html