David has a Samsung Galaxy S8, and recently his GPS started lagging and losing connection with some of his IoT devices. So he bought a new Galaxy S20+. But it's doing the exact same things. Leo says that GPS is a line of sight technology, and you can lose connectivity when the signal is blocked. It'll work better from your windshield dash. When you get into a new area, it could take some time to connect. After this, it builds an almanac of connections that the phone can rely on. So for those first visits, it could take a few minutes. But if it's still taking a long time, then the lag may be an issue with your vehicle or even the location.
Leo recommends using an external GPS Receiver that pairs to your mobile phone via Bluetooth. He got the Dual Electronics XGPS150A. It'll also be faster and more accurate.